1
|
Vera G, Girón R, Martín-Fontelles MI, Abalo R. Radiographic dose-dependency study of loperamide effects on gastrointestinal motor function in the rat. Temporal relationship with nausea-like behavior. Neurogastroenterol Motil 2019; 31:e13621. [PMID: 31117152 DOI: 10.1111/nmo.13621] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 04/09/2019] [Accepted: 04/24/2019] [Indexed: 02/08/2023]
Abstract
BACKGROUND Loperamide is a potent mu opioid receptor agonist available over the counter to treat diarrhea. Although at therapeutic doses loperamide is devoid of central effects, it may exert them if used at high doses or combined with drugs that increase its systemic and/or central bioavailability. Recently, public health and scientific interest on loperamide has increased due to a growing trend of misuse and abuse, and consequent reports on its toxicity. Our aim was to evaluate in the rat the effects of increasing loperamide doses, with increasing likelihood to induce central effects, on gastrointestinal motor function (including gastric dysmotility and nausea-like behavior). METHODS Male Wistar rats received an intraperitoneal injection of vehicle or loperamide (0.1, 1, or 10 mg kg-1 ). Three sets of experiments were performed to evaluate: (a) central effects (somatic nociceptive thresholds, immobility time, core temperature, spontaneous locomotor activity); (b) general gastrointestinal motility (serial X-rays were taken 0-8 hours after intragastric barium administration and analyzed semiquantitatively, morphometrically, and densitometrically); and (c) bedding intake (a rodent indirect marker of nausea). Animals from sets 1 and 3 were used to evaluate gastric dysmotility ex vivo at 2 and 4 hours after administration, respectively. KEY RESULTS Loperamide significantly induced antinociception, hypothermia, and hypolocomotion (but not catalepsy) at high doses and dose-dependently reduced gastrointestinal motor function, with the intestine exhibiting higher sensitivity than the stomach. Whereas bedding intake occurred early and transiently, gastric dysmotility was much more persistent. CONCLUSIONS AND INFERENCES Our results suggest that loperamide-induced nausea and gastric dysmotility might be temporally dissociated.
Collapse
Affiliation(s)
- Gema Vera
- Departamento de Ciencias Básicas de la Salud, Facultad de Ciencias de la Salud, Universidad Rey Juan Carlos, Alcorcón, Spain.,Grupo de Excelencia Investigadora URJC-Banco de Santander-Grupo Multidisciplinar de Investigación y Tratamiento del Dolor (i+DOL), Alcorcón, Spain.,Unidad Asociada I+D+i al Instituto de Química Médica (IQM), Centro Superior de Investigaciones Científicas (CSIC), Madrid, Spain
| | - Rocío Girón
- Departamento de Ciencias Básicas de la Salud, Facultad de Ciencias de la Salud, Universidad Rey Juan Carlos, Alcorcón, Spain.,Grupo de Excelencia Investigadora URJC-Banco de Santander-Grupo Multidisciplinar de Investigación y Tratamiento del Dolor (i+DOL), Alcorcón, Spain.,Unidad Asociada I+D+i al Instituto de Química Médica (IQM), Centro Superior de Investigaciones Científicas (CSIC), Madrid, Spain
| | - María Isabel Martín-Fontelles
- Departamento de Ciencias Básicas de la Salud, Facultad de Ciencias de la Salud, Universidad Rey Juan Carlos, Alcorcón, Spain.,Grupo de Excelencia Investigadora URJC-Banco de Santander-Grupo Multidisciplinar de Investigación y Tratamiento del Dolor (i+DOL), Alcorcón, Spain.,Unidad Asociada I+D+i al Instituto de Química Médica (IQM), Centro Superior de Investigaciones Científicas (CSIC), Madrid, Spain
| | - Raquel Abalo
- Departamento de Ciencias Básicas de la Salud, Facultad de Ciencias de la Salud, Universidad Rey Juan Carlos, Alcorcón, Spain.,Grupo de Excelencia Investigadora URJC-Banco de Santander-Grupo Multidisciplinar de Investigación y Tratamiento del Dolor (i+DOL), Alcorcón, Spain.,Unidad Asociada I+D+i al Instituto de Química Médica (IQM), Centro Superior de Investigaciones Científicas (CSIC), Madrid, Spain
| |
Collapse
|
2
|
Abalo R, Uranga JA, Pérez-García I, de Andrés R, Girón R, Vera G, López-Pérez AE, Martín-Fontelles MI. May cannabinoids prevent the development of chemotherapy-induced diarrhea and intestinal mucositis? Experimental study in the rat. Neurogastroenterol Motil 2017; 29. [PMID: 27686064 DOI: 10.1111/nmo.12952] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2016] [Accepted: 08/24/2016] [Indexed: 12/12/2022]
Abstract
BACKGROUND The antineoplastic drug 5-fluoruracil (5-FU) is a pirimidine analog, which frequently induces potentially fatal diarrhea and mucositis. Cannabinoids reduce gastrointestinal motility and secretion and might prevent 5-FU-induced gut adverse effects. Here, we asked whether cannabinoids may prevent diarrhea and mucositis induced by 5-FU in the rat. METHODS Male Wistar rats received vehicle or the non-selective cannabinoid agonist WIN 55,212-2 (WIN; 0.5 mg kg-1 injection-1 , 1 injection day-1 , 4 consecutive days) by intraperitoneal (ip) route; on the first 2 days, animals received also saline or 5-FU (150 mg kg-1 injection-1 , cumulative dose of 300 mg kg-1 ). Gastrointestinal motor function was radiographically studied after barium contrast intragastric administration on experimental days 1 and 4. Structural alterations of the stomach, small intestine and colon were histologically studied on day 4. PAS staining and immunohistochemistry for Ki67, chromogranin A and CD163 were used to detect secretory, proliferating, and endocrine cells, and activated macrophages respectively. KEY RESULTS As shown radiographically, 5-FU induced significant gastric emptying delay (on days 1 and 4) and diarrhea (on day 4). WIN did not significantly alter the motility curves obtained for either control or 5-FU-treated animals but tended to reduce the severity of 5-FU-induced diarrhea and increased permanence of barium from day 1 to the beginning of day 4 in 5-FU-treated animals. 5-FU-induced mucositis was severe and not counteracted by WIN. CONCLUSIONS AND INFERENCES 5-FU-induced diarrhea, but not mucositis, was partly prevented by WIN at a low dose. Cannabinoids might be useful to prevent chemotherapy-induced diarrhea.
Collapse
Affiliation(s)
- R Abalo
- Departamento de Ciencias Básicas de la Salud, Facultad de Ciencias de la Salud, Universidad Rey Juan Carlos, Madrid, Alcorcón, Spain.,Unidad Asociada I+D+i al Instituto de Investigación en Ciencias de la Alimentación, CIAL (CSIC), Madrid, Spain.,Unidad Asociada I+D+i al Instituto de Química Médica, IQM (CSIC), Madrid, Spain.,Grupo de Excelencia Investigadora URJC-Banco de Santander-Grupo Multidisciplinar de Investigación y Tratamiento del Dolor (i+DOL), Madrid, Spain
| | - J A Uranga
- Departamento de Ciencias Básicas de la Salud, Facultad de Ciencias de la Salud, Universidad Rey Juan Carlos, Madrid, Alcorcón, Spain.,Unidad Asociada I+D+i al Instituto de Investigación en Ciencias de la Alimentación, CIAL (CSIC), Madrid, Spain.,Grupo de Excelencia Investigadora URJC-Banco de Santander-Grupo Multidisciplinar de Investigación y Tratamiento del Dolor (i+DOL), Madrid, Spain
| | - I Pérez-García
- Departamento de Ciencias Básicas de la Salud, Facultad de Ciencias de la Salud, Universidad Rey Juan Carlos, Madrid, Alcorcón, Spain
| | - R de Andrés
- Departamento de Ciencias Básicas de la Salud, Facultad de Ciencias de la Salud, Universidad Rey Juan Carlos, Madrid, Alcorcón, Spain
| | - R Girón
- Departamento de Ciencias Básicas de la Salud, Facultad de Ciencias de la Salud, Universidad Rey Juan Carlos, Madrid, Alcorcón, Spain.,Unidad Asociada I+D+i al Instituto de Investigación en Ciencias de la Alimentación, CIAL (CSIC), Madrid, Spain.,Unidad Asociada I+D+i al Instituto de Química Médica, IQM (CSIC), Madrid, Spain.,Grupo de Excelencia Investigadora URJC-Banco de Santander-Grupo Multidisciplinar de Investigación y Tratamiento del Dolor (i+DOL), Madrid, Spain
| | - G Vera
- Departamento de Ciencias Básicas de la Salud, Facultad de Ciencias de la Salud, Universidad Rey Juan Carlos, Madrid, Alcorcón, Spain.,Unidad Asociada I+D+i al Instituto de Investigación en Ciencias de la Alimentación, CIAL (CSIC), Madrid, Spain.,Unidad Asociada I+D+i al Instituto de Química Médica, IQM (CSIC), Madrid, Spain.,Grupo de Excelencia Investigadora URJC-Banco de Santander-Grupo Multidisciplinar de Investigación y Tratamiento del Dolor (i+DOL), Madrid, Spain
| | - A E López-Pérez
- Grupo de Excelencia Investigadora URJC-Banco de Santander-Grupo Multidisciplinar de Investigación y Tratamiento del Dolor (i+DOL), Madrid, Spain.,Unidad del Dolor, Servicio de Anestesiología, Hospital General Universitario Gregorio Marañón (HGUGM), Madrid, Spain
| | - M I Martín-Fontelles
- Departamento de Ciencias Básicas de la Salud, Facultad de Ciencias de la Salud, Universidad Rey Juan Carlos, Madrid, Alcorcón, Spain.,Unidad Asociada I+D+i al Instituto de Investigación en Ciencias de la Alimentación, CIAL (CSIC), Madrid, Spain.,Unidad Asociada I+D+i al Instituto de Química Médica, IQM (CSIC), Madrid, Spain.,Grupo de Excelencia Investigadora URJC-Banco de Santander-Grupo Multidisciplinar de Investigación y Tratamiento del Dolor (i+DOL), Madrid, Spain
| |
Collapse
|
3
|
Busby RW, Kessler MM, Bartolini WP, Bryant AP, Hannig G, Higgins CS, Solinga RM, Tobin JV, Wakefield JD, Kurtz CB, Currie MG. Pharmacologic properties, metabolism, and disposition of linaclotide, a novel therapeutic peptide approved for the treatment of irritable bowel syndrome with constipation and chronic idiopathic constipation. J Pharmacol Exp Ther 2012; 344:196-206. [PMID: 23090647 DOI: 10.1124/jpet.112.199430] [Citation(s) in RCA: 101] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Linaclotide, a potent guanylate cyclase C agonist, is a therapeutic peptide approved in the United States for the treatment of irritable bowel syndrome with constipation and chronic idiopathic constipation. We present for the first time the metabolism, degradation, and disposition of linaclotide in animals and humans. We examined the metabolic stability of linaclotide in conditions that mimic the gastrointestinal tract and characterized the metabolite MM-419447 (CCEYCCNPACTGC), which contributes to the pharmacologic effects of linaclotide. Systemic exposure to these active peptides is low in rats and humans, and the low systemic and portal vein concentrations of linaclotide and MM-419447 observed in the rat confirmed both peptides are minimally absorbed after oral administration. Linaclotide is stable in the acidic environment of the stomach and is converted to MM-419447 in the small intestine. The disulfide bonds of both peptides are reduced in the small intestine, where they are subsequently proteolyzed and degraded. After oral administration of linaclotide, <1% of the dose was excreted as active peptide in rat feces and a mean of 3-5% in human feces; in both cases MM-419447 was the predominant peptide recovered. MM-419447 exhibits high-affinity binding in vitro to T84 cells, resulting in a significant, concentration-dependent accumulation of intracellular cyclic guanosine-3',5'-monophosphate (cGMP). In rat models of gastrointestinal function, orally dosed MM-419447 significantly increased fluid secretion into small intestinal loops, increased intraluminal cGMP, and caused a dose-dependent acceleration in gastrointestinal transit. These results demonstrate the importance of the active metabolite in contributing to linaclotide's pharmacology.
Collapse
Affiliation(s)
- Robert W Busby
- Ironwood Pharmaceuticals, Inc., 301 Binney Street, Cambridge, MA 02142, USA.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
4
|
Abstract
Diarrhea, a disease of poverty and poor sanitation, kills an estimated two million children each year. Oral rehydration therapy is a very simple and inexpensive treatment that has significantly reduced mortality from secretory diarrhea caused by rotavirus, cholera and enterotoxigenic Escherichia coli. The efficacy and adoption of oral rehydration therapy would be enhanced by a drug that reduces fluid loss associated with these diseases and alleviates disease symptoms. Secretion and absorption by the intestine offer a number of potential drug targets to reduce fluid loss. Among these, the cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel is the most attractive because it is the primary driver of secretion in cases of diarrhea caused by enterotoxigenic bacteria. CFTR can be inhibited by both natural products and synthetic small molecules. iOWH032 is a synthetic CFTR inhibitor that has recently entered clinical trials for this indication.
Collapse
|
5
|
Sun X, Wang X, Wang GD, Xia Y, Liu S, Qu M, Needleman BJ, Mikami DJ, Melvin WS, Bohn LM, Ueno R, Wood JD. Lubiprostone reverses the inhibitory action of morphine on mucosal secretion in human small intestine. Dig Dis Sci 2011; 56:330-8. [PMID: 21181441 PMCID: PMC4757489 DOI: 10.1007/s10620-010-1515-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2010] [Accepted: 11/22/2010] [Indexed: 01/03/2023]
Abstract
BACKGROUND AND AIMS Treatments with morphine or opioid agonists cause constipation. Lubiprostone is approved for treatment of adult idiopathic constipation and constipation-predominant IBS in adult women. We tested whether lubiprostone can reverse morphine-suppression of mucosal secretion in human intestine and explored the mechanism of action. METHODS Fresh segments of jejunum discarded during Roux-En-Y gastric bypass surgeries were used. Changes in short-circuit current (ΔIsc) were recorded in Ussing flux chambers as a marker for electrogenic chloride secretion during pharmacological interactions between morphine, prostaglandin receptor antagonists, chloride channel blockers and lubiprostone. RESULTS Morphine suppressed basal Isc. Lubiprostone reversed morphine suppression of basal Isc. Lubiprostone, applied to the mucosa in concentrations ranging from 3 nM to 30 μM, evoked increases in Isc in concentration-dependent manner when applied to the mucosal side of muscle-stripped preparations. Blockade of enteric nerves did not change stimulation of Isc by lubiprostone. Removal of chloride or application of bumetanide or NPPB suppressed or abolished responses to lubiprostone. Antagonists acting at CFTR channels and prostaglandin EP(4) receptors, but not at E(1), EP(1-3) receptors, partially suppressed stimulation of Isc by lubiprostone. CONCLUSIONS Antisecretory action of morphine results from suppression of excitability of secretomotor neurons in the enteric nervous system. Lubiprostone, which does not affect enteric neurons directly, bypasses the action of morphine by directly opening mucosal chloride channels.
Collapse
Affiliation(s)
- Xiaohong Sun
- Department of Physiology and Cell Biology, The Ohio State University College of Medicine, 304 Hamilton Hall, 1645 Neil Avenue, Columbus, OH 43210, USA
| | - Xiyu Wang
- Department of Anesthesiology, The Ohio State University College of Medicine, Columbus, OH, USA,
| | - Guo-Du Wang
- Department of Physiology and Cell Biology, The Ohio State University College of Medicine, 304 Hamilton Hall, 1645 Neil Avenue, Columbus, OH 43210, USA,
| | - Yun Xia
- Department of Anesthesiology, The Ohio State University College of Medicine, Columbus, OH, USA,
| | - Sumei Liu
- Department of Internal Medicine, The Ohio State University College of Medicine, Columbus, OH, USA; Department of Physiology and Cell Biology, The Ohio State University College of Medicine, 304 Hamilton Hall, 1645 Neil Avenue, Columbus, OH 43210, USA
| | - Meihua Qu
- Department of Physiology and Cell Biology, The Ohio State University College of Medicine, 304 Hamilton Hall, 1645 Neil Avenue, Columbus, OH 43210, USA,
| | - Bradley J. Needleman
- Department of Surgery, The Ohio State University College of Medicine, Columbus, OH, USA,
| | - Dean J. Mikami
- Department of Surgery, The Ohio State University College of Medicine, Columbus, OH, USA,
| | - W. Scott Melvin
- Department of Surgery, The Ohio State University College of Medicine, Columbus, OH, USA,
| | - Laura M. Bohn
- Department of Pharmacology, The Ohio State University College of Medicine, Columbus, OH, USA
| | - Ryuji Ueno
- Sucampo Pharmaceuticals, Inc., Bethesda, MD, USA,
| | - Jackie D. Wood
- Department of Physiology and Cell Biology, The Ohio State University College of Medicine, 304 Hamilton Hall, 1645 Neil Avenue, Columbus, OH 43210, USA
| |
Collapse
|
6
|
Busby RW, Bryant AP, Bartolini WP, Cordero EA, Hannig G, Kessler MM, Mahajan-Miklos S, Pierce CM, Solinga RM, Sun LJ, Tobin JV, Kurtz CB, Currie MG. Linaclotide, through activation of guanylate cyclase C, acts locally in the gastrointestinal tract to elicit enhanced intestinal secretion and transit. Eur J Pharmacol 2010; 649:328-35. [PMID: 20863829 DOI: 10.1016/j.ejphar.2010.09.019] [Citation(s) in RCA: 156] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2010] [Revised: 08/03/2010] [Accepted: 09/07/2010] [Indexed: 02/06/2023]
Abstract
Linaclotide is a first-in-class, orally administered 14-amino acid peptide that is in development for the treatment of irritable bowel syndrome with constipation and chronic constipation. We have characterized the solution structure of linaclotide, the in vitro binding and agonist activity to guanylate cyclase C receptors, the stability of linaclotide under conditions mimicking the gastric environment, oral bioavailability, and the pharmacodynamic effects in rat models of gastrointestinal transit and intestinal secretion. Nuclear magnetic resonance spectroscopy analysis determined that the molecular structure of linaclotide is stabilized by three intramolecular disulfide bridges. Linaclotide exhibited high affinity and pH-independent binding (K(i): 1.23-1.64 nM) to guanylate cyclase C receptors on human colon carcinoma T84 cells and concomitantly, linaclotide binding resulted in a significant, concentration-dependent accumulation of intracellular cyclic guanosine-3', 5'-monophosphate (cGMP) (EC₅₀:99 nM). Linaclotide was stable after 3 h incubation in simulated gastric fluid (pH 1) and similarly, was completely resistant to hydrolysis by pepsin. Pharmacokinetic analysis of linaclotide showed very low oral bioavailability (0.1%). Orally administered linaclotide elicited a significant, dose-dependent increase in gastrointestinal transit rates in rats at doses of ≥5 μg/kg. Exposure of surgically ligated small intestinal loops to linaclotide induced a significant increase in fluid secretion, accompanied by a significant increase in intraluminal cGMP levels. These results suggest that the guanylate cyclase C agonist linaclotide elicits potent pharmacological responses locally in the gastrointestinal tract, and that orally administered guanylate cyclase C agonists may be capable of improving bowel habits in patients suffering from irritable bowel syndrome with constipation and chronic constipation.
Collapse
Affiliation(s)
- Robert W Busby
- Ironwood Pharmaceuticals Inc., 301 Binney Street, Cambridge, MA, 02142, USA.
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
7
|
Fei G, Raehal K, Liu S, Qu MH, Sun X, Wang GD, Wang XY, Xia Y, Schmid CL, Bohn LM, Wood JD. Lubiprostone reverses the inhibitory action of morphine on intestinal secretion in guinea pig and mouse. J Pharmacol Exp Ther 2010; 334:333-40. [PMID: 20406855 DOI: 10.1124/jpet.110.166116] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Lubiprostone activates ClC-2 chloride channels in epithelia. It is approved for treatment of chronic idiopathic constipation in adults and constipation-predominate irritable bowel syndrome in women. We tested a hypothesis that lubiprostone can reverse the constipating action of morphine and investigated the mechanism of action. Short-circuit current (Isc) was recorded in Ussing chambers as a marker for chloride secretion during pharmacological interactions between morphine and lubiprostone. Measurements of fecal wet weight were used to obtain information on morphine-lubiprostone interactions in conscious mice. Morphine decreased basal Isc, with an IC(50) of 96.1 nM. The action of dimethylphenylpiperazinium (DMPP), a nicotinic receptor agonist that stimulates neurogenic Isc, was suppressed by morphine. Lubiprostone applied after pretreatment with morphine reversed morphine suppression of both basal Isc and DMPP-evoked chloride secretion. Electrical field stimulation (EFS) of submucosal neurons evoked biphasic increases in Isc. Morphine abolished the first phase and marginally suppressed the second phase. Lubiprostone reversed, in concentration-dependent manner, the action of morphine on the first and second phases of the EFS-evoked responses. Subcutaneous lubiprostone increased fecal wet weight and numbers of pellets expelled. Morphine significantly reduced fecal wet weight and number of pellets. Injection of lubiprostone, 30-min after morphine, reversed morphine-induced suppression of fecal wet weight. We conclude that inhibitory action of morphine on chloride secretion reflects suppression of excitability of cholinergic secretomotor neurons in the enteric nervous system. Lubiprostone, which does not directly affect enteric neurons, bypasses the neurogenic constipating effects of morphine by directly opening chloride channels in the mucosal epithelium.
Collapse
Affiliation(s)
- Guijun Fei
- Department of Physiology and Cell Biology, College of Medicine, The Ohio State University, Columbus, OH 43210-1218, USA
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
8
|
Shahidul Islam M, Nishiyama A, Sakaguchi E. Sorbitol and lactitol reduce body fat and toxic ammonia levels in rats. Nutr Res 2007. [DOI: 10.1016/j.nutres.2007.04.019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
9
|
Islam MS, Sakaguchi E, Kashima N, Hoshi S. Effect of sugar alcohols on gut function and body composition in normal and cecectomized rats. Exp Anim 2004; 53:361-71. [PMID: 15297710 DOI: 10.1538/expanim.53.361] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The effects of two sugar alcohols on feed utilization, digesta retention, gut fermentation and serum lipid profiles were compared in normal and cecectomized rats to examine the possibility of the cecectomized rat as an experimental animal with relevance to humans. Semi-purified diets containing no sugar alcohol, 7% sorbitol or 7% lactitol were fed to normal and cecectomized rats for 16 days. The digestibility of the crude fat and the compositions of the carcass dry matter and crude fat were significantly decreased by feeding sugar alcohols in both groups, but the effects were relatively higher in the cecectomized rats than in the normal rats. Diarrhea, faster transit times and shorter retention times of digesta were noted in the cecectomized rats fed sugar alcohols, while the inverse results were observed in the normal rats fed similar diets. The concentration of cecal organic acids was increased in the normal rats, whereas the concentration of colonic organic acids was decreased in the cecectomized rats fed sugar alcohols, compared with their corresponding control groups. The concentration of serum total cholesterol was decreased in both the normal and cecectomized rats fed diets containing sugar alcohols. The tendencies for diarrhea, faster digesta transit and reduced body fat induced by the fermentable materials in the cecectomized rat have good relevance to the parallel effects of fermentable materials in humans, suggesting the possibility of using the cecectomized rat as a model to study some of the physiological effects of sugar alcohols in humans.
Collapse
Affiliation(s)
- Md Shahidul Islam
- Laboratory of Animal Nutrition, Faculty of Agriculture, Okayama University, Japan
| | | | | | | |
Collapse
|
10
|
Kadowaki M, Nagakura Y, Tokita K, Hanaoka K, Tomoi M. Adenosine A1 receptor blockade reverses experimental postoperative ileus in rat colon. Eur J Pharmacol 2003; 458:197-200. [PMID: 12498926 DOI: 10.1016/s0014-2999(02)02766-8] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Inhibition of colonic propulsive motility is the main contributor to postoperative ileus in humans. Experimental models for investigating colonic propulsion in surgically induced postoperative ileus have not previously been available. This study was designed to assess whether adenosine A(1) receptor antagonists (R)-1-[(E)-3-(2-phenylpyrazolo[1,5-a]pyridin-3-yl) acryloyl]-piperidin-2-yl acetic acid (FK352) and 8-cyclopentyl-1, 3-dipropylxanthine (DPCPX) reverse the colonic motility disorder in newly developed rat experimental ileus models. When rats underwent anesthesia (pentobarbital) or surgical traumas (partial gastrectomy, cecectomy or gentle touching of the colon with fingers), colonic propulsive motility was evaluated by migration of intracolonically injected dye in awake unrestrained rats. Propulsive motility resulted in significant decrease after the treatment of the anesthesia or partial gastrectomy. Intravenous administration of either adenosine A(1) receptor antagonist reversed the slowed colonic propulsion in these experimental ileus models. The present study suggests that the blockade of adenosine A(1) receptors has therapeutic potential for postoperative ileus.
Collapse
Affiliation(s)
- Makoto Kadowaki
- Pharmacological Research Laboratories, Fujisawa Pharmaceutical Co., Ltd., 532-0031, Osaka, Japan.
| | | | | | | | | |
Collapse
|
11
|
Cui L, Blanchard RK, Cousins RJ. The permissive effect of zinc deficiency on uroguanylin and inducible nitric oxide synthase gene upregulation in rat intestine induced by interleukin 1alpha is rapidly reversed by zinc repletion. J Nutr 2003; 133:51-6. [PMID: 12514266 DOI: 10.1093/jn/133.1.51] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Deficient intake of zinc from the diet upregulates both uroguanylin (UG) and inducible nitric oxide synthase (iNOS) expression in rats. Because these changes influence intestinal fluid secretion and intestinal cell pathophysiology, they relate to the incidence of diarrheal disease and its reversal by zinc as well as intestinal inflammation in general. A model of moderate zinc deficiency in rats, which changes molecular indices of zinc deficiency, was used to further explore the effects of the proinflammatory cytokine interleukin (IL)-1alpha and zinc repletion on these changes. IL-1alpha has been shown to have a role in the intestinal inflammation that occurs with bacterial infection. Our results showed a permissive effect of zinc deficiency on both UG and iNOS expression. Specifically, UG expression was responsive to zinc deficiency and IL-1alpha challenge, which were additive when combined, whereas iNOS expression was upregulated by IL-1alpha only during the deficiency. Immunohistochemistry showed that the increase in UG was limited to enterocytes of the upper villus but, in contrast, the increase in iNOS was principally in cells of the lamina propria of IL-1alpha-treated rats. Cells exhibiting UG upregulation did not co-express serotonin. Repletion with zinc reversed upregulation of the iNOS gene within 1 d, whereas UG upregulation required 3-4 d to return to normal. This differential response to repletion suggests that mechanisms of UG and iNOS dysregulation are different. Dysregulation of both genes may contribute to the severity of zinc-responsive diarrheal disease and intestinal inflammatory disease.
Collapse
Affiliation(s)
- Li Cui
- Food Science and Human Nutrition Department and Center for Nutritional Sciences, University of Florida, Gainesville 32611-0370, USA
| | | | | |
Collapse
|