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Patel D, Baliss M, Saikumar P, Numan L, Teckman J, Hachem C. A Gastroenterologist's Guide to Care Transitions in Cystic Fibrosis from Pediatrics to Adult Care. Int J Mol Sci 2023; 24:15766. [PMID: 37958749 PMCID: PMC10648514 DOI: 10.3390/ijms242115766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 10/04/2023] [Accepted: 10/25/2023] [Indexed: 11/15/2023] Open
Abstract
Cystic Fibrosis is a chronic disease affecting multiple systems, including the GI tract. Clinical manifestation in patients can start as early as infancy and vary across different age groups. With the advent of new, highly effective modulators, the life expectancy of PwCF has improved significantly. Various GI aspects of CF care, such as nutrition, are linked to an overall improvement in morbidity, lung function and the quality of life of PwCF. The variable clinical presentations and management of GI diseases in pediatrics and adults with CF should be recognized. Therefore, it is necessary to ensure efficient transfer of information between pediatric and adult providers for proper continuity of management and coordination of care at the time of transition. The transition of care is a challenging process for both patients and providers and currently there are no specific tools for GI providers to help ensure a smooth transition. In this review, we aim to highlight the crucial features of GI care at the time of transition and provide a checklist that can assist in ensuring an effective transition and ease the challenges associated with it.
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Affiliation(s)
- Dhiren Patel
- Department of Pediatrics, Division of Pediatric Gastroenterology, Hepatology and Nutrition, Cardinal Glennon Children’s Medical Center, Saint Louis University School of Medicine, St. Louis, MO 63104, USA; (P.S.); (J.T.)
- The AHEAD Institute, Saint Louis University School of Medicine, St. Louis, MO 63104, USA
| | - Michelle Baliss
- Department of Gastroenterology and Hepatology, Saint Louis University School of Medicine, St. Louis, MO 63104, USA; (M.B.); (L.N.); (C.H.)
| | - Pavithra Saikumar
- Department of Pediatrics, Division of Pediatric Gastroenterology, Hepatology and Nutrition, Cardinal Glennon Children’s Medical Center, Saint Louis University School of Medicine, St. Louis, MO 63104, USA; (P.S.); (J.T.)
| | - Laith Numan
- Department of Gastroenterology and Hepatology, Saint Louis University School of Medicine, St. Louis, MO 63104, USA; (M.B.); (L.N.); (C.H.)
| | - Jeffrey Teckman
- Department of Pediatrics, Division of Pediatric Gastroenterology, Hepatology and Nutrition, Cardinal Glennon Children’s Medical Center, Saint Louis University School of Medicine, St. Louis, MO 63104, USA; (P.S.); (J.T.)
| | - Christine Hachem
- Department of Gastroenterology and Hepatology, Saint Louis University School of Medicine, St. Louis, MO 63104, USA; (M.B.); (L.N.); (C.H.)
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Demeyer S, De Boeck K, Witters P, Cosaert K. Beyond pancreatic insufficiency and liver disease in cystic fibrosis. Eur J Pediatr 2016; 175:881-94. [PMID: 27055450 DOI: 10.1007/s00431-016-2719-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Revised: 03/17/2016] [Accepted: 03/22/2016] [Indexed: 12/13/2022]
Abstract
UNLABELLED Cystic fibrosis is a life shortening hereditary disease, primarily leading to progressive pulmonary infection and exocrine pancreatic dysfunction. Several gastrointestinal complications other than malabsorption can arise during the disease course and with the progressively increasing life span of patients with CF; new and more rare complications are being recognized. We review the literature on gastrointestinal manifestations in CF, excluding the liver and pancreas. CONCLUSION We describe the clinical presentation and treatment of more common conditions like gastroesophageal reflux, small intestinal bacterial overgrowth, intussusception, meconium ileus, distal intestinal obstruction syndrome, and constipation, and we also discuss what is known on celiac disease, appendicitis, fibrosing colonopathy, inflammation and inflammatory bowel disease and gastrointestinal cancer. WHAT IS KNOWN • Gastrointestinal complications arise early in the course of the disease and have a severe impact on the quality of life of the patients. What is New: • This review is a concise summary of the current literature on gastrointestinal complications of cystic fibrosis. • We focused on clinical presentation and diagnostic investigations and provide a comprehensive resume of the current treatment options.
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Affiliation(s)
- Stephanie Demeyer
- Universitaire Ziekenhuizen Leuven, Leuven, Vlaams-Brabant, Belgium. .,Department of Pediatrics, University Hospital Gasthuisberg, Herestraat 49, Leuven, 3000, Belgium.
| | - Kris De Boeck
- Department of Pediatrics, University Hospital Gasthuisberg, Herestraat 49, Leuven, 3000, Belgium
| | - Peter Witters
- Department of Pediatrics, University Hospital Gasthuisberg, Herestraat 49, Leuven, 3000, Belgium
| | - Katrien Cosaert
- Department of Pharmocology, University Hospital Gasthuisberg, Herestraat 49, Leuven, 3000, Belgium
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Radulovic M, Anand P, Korsten MA, Gong B. Targeting Ion Channels: An Important Therapeutic Implication in Gastrointestinal Dysmotility in Patients With Spinal Cord Injury. J Neurogastroenterol Motil 2015; 21:494-502. [PMID: 26424038 PMCID: PMC4622131 DOI: 10.5056/jnm15061] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2015] [Revised: 06/10/2015] [Accepted: 07/06/2015] [Indexed: 01/04/2023] Open
Abstract
Gastrointestinal (GI) dysmotility is a severe, and common complication in patients with spinal cord injury (SCI). Current therapeutic methods using acetylcholine analogs or laxative agents have unwanted side effects, besides often fail to have desired effect. Various ion channels such as ATP-sensitive potassium (KATP) channel, calcium ions (Ca2+)-activated potassium ions (K+) channels, voltage-sensitive Ca2+ channels and chloride ion (Cl−) channels are abundantly expressed in GI tissues, and play an important role in regulating GI motility. The release of neurotransmitters from the enteric nerve terminal, innervating GI interstitial cells of Cajal (ICC), and smooth muscle cells (SMC), causes inactivation of K+ and Cl− channels, increasing Ca2+ influx into cytoplasm, resulting in membrane depolarization and smooth muscle contraction. Thus, agents directly regulating ion channels activity either in ICC or in SMC may affect GI peristalsis and would be potential therapeutic target for the treatment of GI dysmotility with SCI.
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Affiliation(s)
- Miroslav Radulovic
- Department of Medicine Icahn School of Medicine at Mount Sinai, New York, NY, USA.,National Center of Excellence for the Medical Consequences of SCI, James J Peters Veteran Affairs Medical Center, Bronx, NY, USA
| | - Preeti Anand
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Mark A Korsten
- Department of Medicine Icahn School of Medicine at Mount Sinai, New York, NY, USA.,National Center of Excellence for the Medical Consequences of SCI, James J Peters Veteran Affairs Medical Center, Bronx, NY, USA
| | - Bing Gong
- Department of Medicine Icahn School of Medicine at Mount Sinai, New York, NY, USA.,Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
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Wilson N, Schey R. Lubiprostone in constipation: clinical evidence and place in therapy. Ther Adv Chronic Dis 2015; 6:40-50. [PMID: 25729555 DOI: 10.1177/2040622314567678] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Constipation is one of the most common function bowel disorders encountered by primary care providers and gastroenterologists. Disorders of chronic constipation, including irritable bowel syndrome with constipation, chronic idiopathic constipation, and opioid-induced chronic constipation, are associated with significant medical costs and a negative impact on quality of life. Although there is evidence supporting the effectiveness of some over-the-counter laxatives in chronic constipation, currently there is no evidence supporting lifestyle modification, dietary change or over-the-counter laxatives as effective long-term therapy for patients with chronic constipation. Lubiprostone is a prostaglandin-derived bicyclic fatty acid available to use for long-term treatment of constipation. Lubiprostone works by increasing intraluminal chloride ion secretion, which results in a passive influx of water and sodium, leading to increased intestinal peristalsis and colonic laxation with decreased intestinal stool transit time. Randomized, double-blind, placebo-controlled trials of lubiprostone in patients with chronic constipation, irritable bowel syndrome and opioid-induced constipation have shown it to be effective and free of serious adverse effects. The most common side effects associated with lubiprostone are mild to moderate nausea and diarrhea. Currently lubiprostone is approved for treatment of chronic constipation and opioid-induced constipation for men and women at 24 µg twice daily and for treatment of irritable bowel syndrome with constipation in women at 8 µg twice daily. Additional research continues to shed light on the molecular mechanisms of lubiprostone and further work may expand its clinical applications.
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Affiliation(s)
- Nicholas Wilson
- Section of Gastroenterology, Department of Medicine, Temple University School of Medicine, Philadelphia, PA, USA
| | - Ron Schey
- Neurogastroenterology & Esophageal Disorders Program, Temple University Physicians/Section of Gastroenterology, 3401 N Broad Street, Philadelphia, PA 19140, USA
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Abstract
The clinical manifestations of cystic fibrosis (CF) result from dysfunction of the cystic fibrosis transmembrane regulator protein (CFTR). The majority of people with CF have a limited life span as a consequence of CFTR dysfunction in the respiratory tract. However, CFTR dysfunction in the gastrointestinal (GI) tract occurs earlier in ontogeny and is present in all patients, regardless of genotype. The same pathophysiologic triad of obstruction, infection, and inflammation that causes disease in the airways also causes disease in the intestines. This article describes the effects of CFTR dysfunction on the intestinal tissues and the intraluminal environment. Mouse models of CF have greatly advanced our understanding of the GI manifestations of CF, which can be directly applied to understanding CF disease in humans.
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Affiliation(s)
- Robert C De Lisle
- Anatomy and Cell Biology, University of Kansas School of Medicine, Kansas City, Kansas 66160
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Chan WW, Mashimo H. Lubiprostone Increases Small Intestinal Smooth Muscle Contractions Through a Prostaglandin E Receptor 1 (EP1)-mediated Pathway. J Neurogastroenterol Motil 2013; 19:312-8. [PMID: 23875097 PMCID: PMC3714408 DOI: 10.5056/jnm.2013.19.3.312] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2013] [Revised: 04/18/2013] [Accepted: 04/19/2013] [Indexed: 12/28/2022] Open
Abstract
Background/Aims Lubiprostone, a chloride channel type 2 (ClC-2) activator, was thought to treat constipation by enhancing intestinal secretion. It has been associated with increased intestinal transit and delayed gastric emptying. Structurally similar to prostones with up to 54% prostaglandin E2 activity on prostaglandin E receptor 1 (EP1), lubiprostone may also exert EP1-mediated procontractile effect on intestinal smooth muscles. We investigated lubiprostone's effects on intestinal smooth muscle contractions and pyloric sphincter tone. Methods Isolated murine small intestinal (longitudinal and circular) and pyloric tissues were mounted in organ baths with modified Krebs solution for isometric recording. Basal muscle tension and response to electrical field stimulation (EFS; 2 ms pulses/10 V/6 Hz/30 sec train) were measured with lubiprostone (10-10-10-5 M) ± EP1 antagonist. Significance was established using Student t test and P < 0.05. Results Lubiprostone had no effect on the basal tension or EFS-induced contractions of longitudinal muscles. With circular muscles, lubiprostone caused a dose-dependent increase in EFS-induced contractions (2.11 ± 0.88 to 4.43 ± 1.38 N/g, P = 0.020) that was inhibited by pretreatment with EP1 antagonist (1.69 ± 0.70 vs. 4.43 ± 1.38 N/g, P = 0.030). Lubiprostone had no effect on circular muscle basal tension, but it induced a dose-dependent increase in pyloric basal tone (1.07 ± 0.01 to 1.97 ± 0.86 fold increase, P < 0.05) that was inhibited by EP1 antagonist. Conclusions In mice, lubiprostone caused a dose-dependent and EP1-mediated increase in contractility of circular but not longitudinal small intestinal smooth muscles, and in basal tone of the pylorus. These findings suggest another mechanism for lubiprostone's observed clinical effects on gastrointestinal motility.
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Affiliation(s)
- Walter W Chan
- Division of Gastroenterology, Hepatology and Endoscopy, Brigham and Women's Hospital, Boston, MA, USA. ; Harvard Medical School, Boston, MA, USA
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Gelfond D, Borowitz D. Gastrointestinal complications of cystic fibrosis. Clin Gastroenterol Hepatol 2013; 11:333-42; quiz e30-1. [PMID: 23142604 DOI: 10.1016/j.cgh.2012.11.006] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2012] [Revised: 10/30/2012] [Accepted: 11/01/2012] [Indexed: 02/07/2023]
Abstract
The cystic fibrosis transmembrane regulator protein (CFTR) is an ion channel in the apical surface of epithelial membranes that regulates other ion channels. Dysfunction of CFTR leads to the clinical entity of CF when mutations in CFTR are inherited in an autosomal recessive fashion. Although airway obstruction, inflammation, and infection are usually the most serious consequences of CFTR dysfunction because they lead to respiratory failure, CFTR dysfunction affects the intestinal tract and the pancreatic and hepatobiliary ducts in a similar fashion, leading to significant morbidity. This review outlines pathophysiology and common gastrointestinal ailments in the CF population along with current medical and surgical management.
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Affiliation(s)
- Daniel Gelfond
- Department of Pediatrics, State University of New York at Buffalo, Buffalo, New York, USA.
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Lubiprostone targets prostanoid signaling and promotes ion transporter trafficking, mucus exocytosis, and contractility. Dig Dis Sci 2012; 57:2826-45. [PMID: 22923315 PMCID: PMC3482986 DOI: 10.1007/s10620-012-2352-8] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2012] [Accepted: 07/28/2012] [Indexed: 12/12/2022]
Abstract
BACKGROUND AND AIM Lubiprostone is a chloride channel activator in clinical use for the treatment of chronic constipation, but the mechanisms of action of the drug are poorly understood. The aim of this study was to determine whether lubiprostone exerts secretory effects in the intestine by membrane trafficking of ion transporters and associated machinery. METHODS Immunolabeling and quantitative fluorescence intensity were used to examine lubiprostone-induced trafficking of the cystic fibrosis transmembrane conductance regulator (CFTR), sodium/potassium-coupled chloride co-transporter 1 (NKCC1), electrogenic sodium/bicarbonate co-transporter 1 (NBCe1), down-regulated in adenoma (DRA), putative anion transporter 1 (PAT1), sodium/proton exchanger 3 (NHE3), Ca(2+) activated chloride channel 2 (ClC-2) serotonin and its transporter SERT, E prostanoid receptors EP4 and EP1, sodium/potassium ATPase (Na-K-ATPase) and protein kinase A (PKA). The effects of lubiprostone on mucus exocytosis in rat intestine and human rectosigmoid explants were also examined. RESULTS Lubiprostone induced contraction of villi and proximal colonic plicae and membrane trafficking of transporters that was more pronounced in villus/surface cells compared to the crypt. Membrane trafficking was determined by: (1) increased membrane labeling for CFTR, PAT1, NKCC1, and NBCe1 and decreased membrane labeling for NHE3, DRA and ClC-2; (2) increased serotonin, SERT, EP4, EP1 and PKA labeling in enterochromaffin cells; (3) increased SERT, EP4, EP1, PKA and Na-K-ATPase in enterocytes; and (4) increased mucus exocytosis in goblet cells. CONCLUSION These data suggest that lubiprostone can target serotonergic, EP4/PKA and EP1 signaling in surface/villus regions; stimulate membrane trafficking of CFTR/NBCe1/NKCC1 in villus epithelia and PAT1/NBCe1/NKCC1 in colonic surface epithelia; suppress NHE3/DRA trafficking and fluid absorption; and enhance mucus-mobilization and mucosal contractility.
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Akiba Y, Kaunitz JD. May the truth be with you: lubiprostone as EP receptor agonist/ClC-2 internalizing "inhibitor". Dig Dis Sci 2012; 57:2740-2. [PMID: 23001408 DOI: 10.1007/s10620-012-2410-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
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Norimatsu Y, Moran AR, MacDonald KD. Lubiprostone activates CFTR, but not ClC-2, via the prostaglandin receptor (EP(4)). Biochem Biophys Res Commun 2012; 426:374-9. [PMID: 22960173 DOI: 10.1016/j.bbrc.2012.08.097] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2012] [Accepted: 08/21/2012] [Indexed: 11/19/2022]
Abstract
The goal of this study was to determine the mechanism of lubiprostone activation of epithelial chloride transport. Lubiprostone is a bicyclic fatty acid approved for the treatment of constipation [1]. There is uncertainty, however, as to how lubiprostone increases epithelial chloride transport. Direct stimulation of ClC-2 and CFTR chloride channels as well as stimulation of these channels via the EP(4) receptor has been described [2-5]. To better define this mechanism, two-electrode voltage clamp was used to assay Xenopus oocytes expressing ClC-2, with or without co-expression of the EP(4) receptor or β adrenergic receptor (βAR), for changes in conductance elicited by lubiprostone. Oocytes co-expressing CFTR and either βAR or the EP(4) receptor were also studied. In oocytes co-expressing ClC-2 and βAR conductance was stimulated by hyperpolarization and acidic pH (pH = 6), but there was no response to the β adrenergic agonist, isoproterenol. Oocytes expressing ClC-2 only or co-expressing ClC-2 and EP(4) did not respond to the presence of 0.1, 1, or 10 μM lubiprostone in the superperfusate. Oocytes co-expressing CFTR and βAR did not respond to hyperpolarization, acidic pH, or 1 μM lubiprostone. However, conductance was elevated by isoproterenol and inhibited by CFTR(inh)172. Co-expression of CFTR and EP(4) resulted in lubiprostone-stimulated conductance, which was also sensitive to CFTR(inh)172. The EC(50) for lubiprostone mediated CFTR activation was ~10 nM. These results demonstrate no direct action of lubiprostone on either ClC-2 or CFTR channels expressed in oocytes. However, the results confirm that CFTR can be activated by lubiprostone via the EP(4) receptor in oocytes.
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Affiliation(s)
- Yohei Norimatsu
- Department of Physiology - Pharmacology, Oregon Health and Science University, OR 97239, USA
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O'Brien CE, Anderson PJ, Stowe CD. Lubiprostone for Constipation in Adults with Cystic Fibrosis: A Pilot Study. Ann Pharmacother 2011; 45:1061-6. [DOI: 10.1345/aph.1q219] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Affiliation(s)
- Catherine E O'Brien
- Department of Pharmacy Practice, College of Pharmacy, University of Arkansas for Medical Sciences, Little Rock, AR
| | - Paula J Anderson
- Department of Internal Medicine, Division of Pulmonary and Critical Care Medicine, College of Medicine, University of Arkansas for Medical Sciences
| | - Cindy D Stowe
- Department of Pharmacy Practice, College of Pharmacy, University of Arkansas for Medical Sciences
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Schey R, Rao SSC. Lubiprostone for the treatment of adults with constipation and irritable bowel syndrome. Dig Dis Sci 2011; 56:1619-25. [PMID: 21523369 DOI: 10.1007/s10620-011-1702-2] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2011] [Accepted: 03/29/2011] [Indexed: 12/14/2022]
Abstract
Chronic constipation and IBS-C are two of the most common functional bowel disorders encountered by primary care providers and gastroenterologists, affecting up to 27% of the population in Western countries [1-4]. The treatment of these disorders is often empiric and most current therapies are indicated for episodic constipation. Over time, most patients become refractory to one or more laxatives. Lubiprostone (Amitiza) has been approved by the US Food and Drug Administration (FDA) for the treatment of chronic-idiopathic constipation [6]. It is an oral bicyclic fatty acid that selectively activates type 2 chloride channels in the apical membrane of the intestinal epithelial cells, hence stimulating chloride secretion, along with passive secretion of sodium and water, inducing peristalsis and laxation, without stimulating gastrointestinal smooth muscle. Several trials have shown it to be effective in the treatment of chronic idiopathic constipation, and recently also IBS-C. It has little systemic absorption and almost free of any serious adverse effects, however, occasionally can cause nausea. Based on the available evidence, it is reasonable to conclude that lubiprostone should be added to the short list of evidence-based pharmacotherapies for chronic constipation and IBS-C. Given the overlap between chronic constipation and IBS-C, clinicians can consider two strategies when deciding on the initial dose of lubiprostone. Based on current product labeling, it is recommended that 8 μg bid be started in patients with IBS-C whereas 24 μg bid be used in those with chronic constipation. Thus far, lubiprostone offers a novel approach to our therapeutic armamentarium, however, there is a need for more drugs with different mechanisms of action, in order to treat constipation that is often multifunctional.
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Affiliation(s)
- Ron Schey
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, University of Iowa Hospitals and Clinics, 200 Hawkins Drive, 4576 JCP, Iowa City, IA 52242, USA.
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De Lisle RC, Mueller R, Roach E. Lubiprostone ameliorates the cystic fibrosis mouse intestinal phenotype. BMC Gastroenterol 2010; 10:107. [PMID: 20843337 PMCID: PMC2945989 DOI: 10.1186/1471-230x-10-107] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2010] [Accepted: 09/15/2010] [Indexed: 12/16/2022] Open
Abstract
Background Cystic fibrosis (CF) is caused by mutations in the CFTR gene that impair the function of CFTR, a cAMP-regulated anion channel. In the small intestine loss of CFTR function creates a dehydrated, acidic luminal environment which is believed to cause an accumulation of mucus, a phenotype characteristic of CF. CF mice have small intestinal bacterial overgrowth, an altered innate immune response, and impaired intestinal transit. We investigated whether lubiprostone, which can activate the CLC2 Cl- channel, would improve the intestinal phenotype in CF mice. Methods Cftrtm1UNC (CF) and wildtype (WT) littermate mice on the C57BL/6J background were used. Lubiprostone (10 μg/kg-day) was administered by gavage for two weeks. Mucus accumulation was estimated from crypt lumen widths in periodic acid-Schiff base, Alcian blue stained sections. Luminal bacterial load was measured by qPCR for the bacterial 16S gene. Gastric emptying and small intestinal transit in fasted mice were assessed using gavaged rhodamine dextran. Gene expression was evaluated by Affymetrix Mouse430 2.0 microarray and qRT-PCR. Results Crypt width in control CF mice was 700% that of WT mice (P < 0.001). Lubiprostone did not affect WT crypt width but, unexpectedly, increased CF crypt width 22% (P = 0.001). Lubiprostone increased bacterial load in WT mice to 490% of WT control levels (P = 0.008). Conversely, lubiprostone decreased bacterial overgrowth in CF mice by 60% (P = 0.005). Lubiprostone increased gastric emptying at 20 min postgavage in both WT (P < 0.001) and CF mice (P < 0.001). Lubiprostone enhanced small intestinal transit in WT mice (P = 0.024) but not in CF mice (P = 0.377). Among other innate immune markers, expression of mast cell genes was elevated 4-to 40-fold in the CF intestine as compared to WT, and lubiprostone treatment of CF mice decreased expression to WT control levels. Conclusions These results indicate that lubiprostone has some benefits for the CF intestinal phenotype, especially on bacterial overgrowth and the innate immune response. The unexpected observation of increased mucus accumulation in the crypts of lubiprostone-treated CF mice suggests the possibility that lubiprostone increases mucus secretion.
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Affiliation(s)
- Robert C De Lisle
- Anatomy & Cell Biology, University of Kansas School of Medicine, Kansas City, KS 66160, USA.
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