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Naik DA, Matonis S, Balakrishnan G, Bettinger CJ. Intestinal retentive systems - recent advances and emerging approaches. J Mater Chem B 2023; 12:64-78. [PMID: 38047746 DOI: 10.1039/d3tb01842c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
Intestinal retentive devices (IRDs) are devices designed to anchor within the lumen of the intestines for long-term residence in the gastrointestinal tract. IRDs can enable impactful medical device technologies including sustained oral drug delivery systems, indwelling sensors, or real-time diagnostics. The design and testing of IRDs present a myriad of challenges, including precise deployment of the device at desired intestinal locations, secure anchoring within the gastrointestinal tract to allow for natural function, and safe removal of the IRD at user-defined times. Advancing the state-of-the-art of IRD is an interdisciplinary effort that requires innovations such as new materials, novel anchoring mechanisms, and medical device design with consistent input from clinical practitioners and end-users. This perspective briefly reviews the current state-of-the-art for IRDs and charts a path forward to inform the design of future concepts. Specifically, this article will highlight materials, retention mechanisms, and test beds to measure the efficacy of IRDs and their mechanisms. Finally, potential synergies between IRD and other medical device technologies are presented to identify future opportunities.
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Affiliation(s)
- Durva A Naik
- Materials Science and Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Wean Hall 3325, Pittsburgh, PA 15213, USA.
| | - Spencer Matonis
- Materials Science and Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Wean Hall 3325, Pittsburgh, PA 15213, USA.
| | - Gaurav Balakrishnan
- Materials Science and Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Wean Hall 3325, Pittsburgh, PA 15213, USA.
| | - Christopher J Bettinger
- Materials Science and Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Wean Hall 3325, Pittsburgh, PA 15213, USA.
- Biomedical Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Scott Hall 4N201, Pittsburgh, PA 15213, USA
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Naik D, Balakrishnan G, Rajagopalan M, Huang X, Trivedi N, Bhat A, Bettinger CJ. Villi Inspired Mechanical Interlocking for Intestinal Retentive Devices. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2301084. [PMID: 37449425 PMCID: PMC10602537 DOI: 10.1002/advs.202301084] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 06/08/2023] [Indexed: 07/18/2023]
Abstract
Intestinal retentive devices have applications ranging from sustained oral drug delivery systems to indwelling ingestible medical devices. Current strategies to retain devices in the small intestine primarily focus on chemical anchoring using mucoadhesives or mechanical coupling using expandable devices or structures that pierce the intestinal epithelium. Here, the feasibility of intestinal retention using devices containing villi-inspired structures that mechanically interlock with natural villi of the small intestine is evaluated. First the viability of mechanical interlocking as an intestinal retention strategy is estimated by estimating the resistance to peristaltic shear between simulated natural villi and devices with various micropost geometries and parameters. Simulations are validated in vitro by fabricating micropost array patches via multistep replica molding and performing lap-shear tests to evaluate the interlocking performance of the fabricated microposts with artificial villi. Finally, the optimal material and design parameters of the patches that can successfully achieve retention in vivo are predicted. This study represents a proof-of-concept for the viability of micropost-villi mechanical interlocking strategy to develop nonpenetrative multifunctional intestinal retentive devices for the future.
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Affiliation(s)
- Durva Naik
- Materials Science and Engineering DepartmentCarnegie Mellon University5000 Forbes Avenue, Wean Hall, 3325PittsburghPA15213USA
| | - Gaurav Balakrishnan
- Materials Science and Engineering DepartmentCarnegie Mellon University5000 Forbes Avenue, Wean Hall, 3325PittsburghPA15213USA
| | - Mahathy Rajagopalan
- Biomedical Engineering DepartmentCarnegie Mellon University5000 Forbes Avenue, Scott Hall, 4N201PittsburghPA15213USA
| | - Xiaozili Huang
- Materials Science and Engineering DepartmentCarnegie Mellon University5000 Forbes Avenue, Wean Hall, 3325PittsburghPA15213USA
| | - Nihar Trivedi
- Materials Science and Engineering DepartmentCarnegie Mellon University5000 Forbes Avenue, Wean Hall, 3325PittsburghPA15213USA
| | - Arnav Bhat
- Biomedical Engineering DepartmentCarnegie Mellon University5000 Forbes Avenue, Scott Hall, 4N201PittsburghPA15213USA
| | - Christopher J. Bettinger
- Materials Science and Engineering DepartmentCarnegie Mellon University5000 Forbes Avenue, Wean Hall, 3325PittsburghPA15213USA
- Biomedical Engineering DepartmentCarnegie Mellon University5000 Forbes Avenue, Scott Hall, 4N201PittsburghPA15213USA
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Nagarajappa P, Chavali SM, Mylavarapu M. Pathological Manifestations of Gluten-Related Neuro-Psychiatric Disorders and the Impact of Gluten-Free Diet in a Pediatric Age Group: A Systematic Review. Cureus 2023; 15:e47062. [PMID: 38022342 PMCID: PMC10644809 DOI: 10.7759/cureus.47062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/15/2023] [Indexed: 12/01/2023] Open
Abstract
Gluten, as a term, causes unease among a vast majority of the population. The reason is the body's inability to process gluten, causing various pathological manifestations. While celiac disease is predominantly a gastrointestinal disease, it also has various extra-intestinal manifestations. Many children receive diagnoses of idiopathic neuropsychiatric symptoms such as epilepsy, attention-deficit hyperactivity disorder (ADHD), restless leg syndrome (RLS), and peripheral neuropathy without ever finding the root cause. A majority of these cases may be associated with celiac disease if only their antibody titers and other appropriate investigations were conducted. The treatment of these manifestations may be eliminated or at least controllable with dietary modification to a gluten-free diet (GFD). In this paper, we will discuss the pathology of celiac disease and the impact of GFD on the neuropsychiatric aspects of this disease, which is of higher prevalence in the pediatric population. A comprehensive literature search was conducted in prominent databases, namely PubMed and Google Scholar, to include studies that provided individual-level data on the neuropathological manifestations and the impact of a GFD on extra-intestinal manifestations of celiac disease. The research protocol was registered in the PROSPERO database (International Prospective Register of Systematic Reviews) with the registration ID: CRD42023415100. Based on the inclusion and exclusion criteria, we included prospective studies, observational studies, and case reports on pediatric patients with biopsy-proven celiac disease, serologically positive celiac disease, celiac disease with neuropsychiatric manifestations, and studies reporting the impact of GFD. After a rigorous quality assessment to remove the risk of bias, we finally included 20 studies to be discussed. In 6 (30%) studies, patients with neuropsychiatric manifestations had positive serology findings and a relatively higher grade of biopsy results. Seven studies discussed the positive impact of GFD. Five of these seven studies reported statistically significant results (p ≤ 0.001). Our study suggests that gluten plays a role in the severity of neuropsychiatric manifestations of celiac disease. Considering the results of our study, we can see that GFD does impact the prognosis of the disease. Neuropsychiatric findings without gastrointestinal manifestations are more common in the pediatric age group. We have clear evidence that several neurological conditions (neuropathy, ADHD, epilepsy, and RLS) have not only a significant association with gluten but can also potentially benefit from GFD. Thus, screening, with a combination of serological, biopsy, and imaging techniques, must be adapted into the guidelines for early detection and induction of GFD. Furthermore, studies should aim at introducing GFD in the pediatric population as a mode of primary prevention. In conclusion, our review underscores the importance of gluten while dealing with idiopathic neurological conditions in children and hopes to shed light on this commonly misdiagnosed and easily manageable disease.
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Affiliation(s)
- Prajwala Nagarajappa
- Department of Pathology, Mysore Medical College and Research Institute, Mysore, IND
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Khalighi Sikaroudi M, Saraf-Bank S, Clayton ZS, Soltani S. A positive effect of egg consumption on macular pigment and healthy vision: a systematic review and meta-analysis of clinical trials. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2021; 101:4003-4009. [PMID: 33491232 DOI: 10.1002/jsfa.11109] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Revised: 12/25/2020] [Accepted: 01/24/2021] [Indexed: 06/12/2023]
Abstract
Increasing macular pigment optical density (MPOD) as a result of increased macular concentration of lutein and zeaxanthin may reduce the risk of age-related macular degeneration (AMD). The aim of the present study was to determine whether the consumption of eggs, a rich source of dietary lutein and zeaxanthin, influences MPOD and serum lutein. In this systematic review and meta-analysis we searched PubMed, Scopus, and ISI Web of Science up to July 2020, for relevant randomized clinical trials. Using a random-effects model, pooled weighted mean differences, and standard deviations (SDs) for each outcome were obtained. The quality of the eligible studies was assessed by the Cochrane Collaboration's tool. A meta-analysis of five trials (296 participants) revealed that egg consumption significantly increased MPOD (weighted mean differences (WMD): +0.037; 95% CI: 0.004, 0.069; P = 0.027) and serum lutein (WMD: +0.150 μmol L̂-1; 95% CI: 0.037, 0.263; P = 0.009). Subgroup analyses showed that egg consumption: (a) had a larger effect on MPOD in studies with a parallel design; and (b) increased serum lutein to a greater extent in a healthy population. We did not detect any heterogeneity between studies. Daily egg consumption has beneficial effects on MPOD and serum lutein is inversely associated with reduced AMD progression. Further clinical trials are required to confirm the results of this study. © 2021 Society of Chemical Industry.
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Affiliation(s)
| | - Sahar Saraf-Bank
- Food Security Research Center, Department of Community Nutrition, School of Nutrition and Food Science, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Zachary S Clayton
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA
| | - Sepideh Soltani
- Nutrition and Food Security Research Center, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
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Bures J, Tacheci I, Kvetina J, Radochova V, Prchal L, Kohoutova D, Valis M, Novak M, Dolezal R, Kopacova M, Rejchrt S, Sestak V, Knoblochova V, Peterova E, Zdarova Karasova J. The Impact of Dextran Sodium Sulfate-Induced Gastrointestinal Injury on the Pharmacokinetic Parameters of Donepezil and Its Active Metabolite 6- O-desmethyldonepezil, and Gastric Myoelectric Activity in Experimental Pigs. Molecules 2021; 26:2160. [PMID: 33918638 PMCID: PMC8070437 DOI: 10.3390/molecules26082160] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2021] [Revised: 04/05/2021] [Accepted: 04/07/2021] [Indexed: 02/07/2023] Open
Abstract
Gastrointestinal side effects of donepezil, including dyspepsia, nausea, vomiting or diarrhea, occur in 20-30% of patients. The pathogenesis of these dysmotility associated disorders has not been fully clarified yet. Pharmacokinetic parameters of donepezil and its active metabolite 6-O-desmethyldonepezil were investigated in experimental pigs with and without small intestinal injury induced by dextran sodium sulfate (DSS). Morphological features of this injury were evaluated by a video capsule endoscopy. The effect of a single and repeated doses of donepezil on gastric myoelectric activity was assessed. Both DSS-induced small intestinal injury and prolonged small intestinal transit time caused higher plasma concentrations of donepezil in experimental pigs. This has an important implication for clinical practice in humans, with a need to reduce doses of the drug if an underlying gastrointestinal disease is present. Donepezil had an undesirable impact on porcine myoelectric activity. This effect was further aggravated by DSS-induced small intestinal injury. These findings can explain donepezil-associated dyspepsia in humans.
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Affiliation(s)
- Jan Bures
- 2nd Department of Internal Medicine-Gastroenterology, Charles University Faculty of Medicine in Hradec Kralove and University Hospital, 500 03 Hradec Kralove, Czech Republic; (I.T.); (J.K.); (D.K.); (M.K.); (S.R.); (V.K.); (E.P.)
| | - Ilja Tacheci
- 2nd Department of Internal Medicine-Gastroenterology, Charles University Faculty of Medicine in Hradec Kralove and University Hospital, 500 03 Hradec Kralove, Czech Republic; (I.T.); (J.K.); (D.K.); (M.K.); (S.R.); (V.K.); (E.P.)
| | - Jaroslav Kvetina
- 2nd Department of Internal Medicine-Gastroenterology, Charles University Faculty of Medicine in Hradec Kralove and University Hospital, 500 03 Hradec Kralove, Czech Republic; (I.T.); (J.K.); (D.K.); (M.K.); (S.R.); (V.K.); (E.P.)
| | - Vera Radochova
- Animal Laboratory, Faculty of Military Health Sciences, University of Defence, 500 01 Hradec Kralove, Czech Republic;
| | - Lukas Prchal
- Centre of Biomedical Research, University Hospital, 500 05 Hradec Kralove, Czech Republic; (L.P.); (M.N.); (R.D.); (J.Z.K.)
| | - Darina Kohoutova
- 2nd Department of Internal Medicine-Gastroenterology, Charles University Faculty of Medicine in Hradec Kralove and University Hospital, 500 03 Hradec Kralove, Czech Republic; (I.T.); (J.K.); (D.K.); (M.K.); (S.R.); (V.K.); (E.P.)
- The Royal Marsden Hospital NHS Foundation Trust, London SW3 6JJ, UK
| | - Martin Valis
- Department of Neurology, Charles University Faculty of Medicine in Hradec Kralove and University Hospital, 500 03 Hradec Kralove, Czech Republic;
| | - Martin Novak
- Centre of Biomedical Research, University Hospital, 500 05 Hradec Kralove, Czech Republic; (L.P.); (M.N.); (R.D.); (J.Z.K.)
- Department of Pharmaceutical Chemistry and Pharmaceutical Analysis, Charles University Faculty of Pharmacy, 500 05 Hradec Kralove, Czech Republic
| | - Rafael Dolezal
- Centre of Biomedical Research, University Hospital, 500 05 Hradec Kralove, Czech Republic; (L.P.); (M.N.); (R.D.); (J.Z.K.)
| | - Marcela Kopacova
- 2nd Department of Internal Medicine-Gastroenterology, Charles University Faculty of Medicine in Hradec Kralove and University Hospital, 500 03 Hradec Kralove, Czech Republic; (I.T.); (J.K.); (D.K.); (M.K.); (S.R.); (V.K.); (E.P.)
| | - Stanislav Rejchrt
- 2nd Department of Internal Medicine-Gastroenterology, Charles University Faculty of Medicine in Hradec Kralove and University Hospital, 500 03 Hradec Kralove, Czech Republic; (I.T.); (J.K.); (D.K.); (M.K.); (S.R.); (V.K.); (E.P.)
| | - Vit Sestak
- Department of Clinical Biochemistry and Diagnostics, University Hospital Hradec Kralove, 500 05 Hradec Kralove, Czech Republic;
| | - Veronika Knoblochova
- 2nd Department of Internal Medicine-Gastroenterology, Charles University Faculty of Medicine in Hradec Kralove and University Hospital, 500 03 Hradec Kralove, Czech Republic; (I.T.); (J.K.); (D.K.); (M.K.); (S.R.); (V.K.); (E.P.)
| | - Eva Peterova
- 2nd Department of Internal Medicine-Gastroenterology, Charles University Faculty of Medicine in Hradec Kralove and University Hospital, 500 03 Hradec Kralove, Czech Republic; (I.T.); (J.K.); (D.K.); (M.K.); (S.R.); (V.K.); (E.P.)
| | - Jana Zdarova Karasova
- Centre of Biomedical Research, University Hospital, 500 05 Hradec Kralove, Czech Republic; (L.P.); (M.N.); (R.D.); (J.Z.K.)
- Department of Toxicology and Military Pharmacy, Faculty of Military Health Sciences, University of Defence, 500 01 Hradec Kralove, Czech Republic
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Lee S, Choi YS, Jo K, Yong HI, Jeong HG, Jung S. Improvement of meat protein digestibility in infants and the elderly. Food Chem 2021; 356:129707. [PMID: 33873143 DOI: 10.1016/j.foodchem.2021.129707] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 02/24/2021] [Accepted: 03/23/2021] [Indexed: 01/11/2023]
Abstract
Meat is a valuable protein source with a balanced composition of essential amino acids and various nutrients. This review aims to identify methods to improve digestion of meat proteins, as well as evaluate the digestive characteristics of infants and the elderly. Immature digestive conditions in infants, including a high gastric pH and low protease concentration, can hinder protein digestion, thus resulting in inhibited growth and development. Likewise, gastrointestinal (GI) tract aging and chronic health problems, including tooth loss and atrophic gastritis, can lead to reduction in protein digestion and absorption in the elderly compared with those in young adults. Moderate heating and several non-thermal technologies, such as aging, enzymatic hydrolysis, ultrasound, high-pressure processing, and pulsed electric field can alter protein structure and improve protein digestion in individuals with low digestive capacity.
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Affiliation(s)
- Seonmin Lee
- Division of Animal and Dairy Science, Chungnam National University, Daejeon 34134, South Korea
| | - Yun-Sang Choi
- Research Group of Food Processing, Korea Food Research Institute, Wanju 55365, South Korea
| | - Kyung Jo
- Division of Animal and Dairy Science, Chungnam National University, Daejeon 34134, South Korea
| | - Hae In Yong
- Research Group of Food Processing, Korea Food Research Institute, Wanju 55365, South Korea
| | - Hyun Gyung Jeong
- Division of Animal and Dairy Science, Chungnam National University, Daejeon 34134, South Korea
| | - Samooel Jung
- Division of Animal and Dairy Science, Chungnam National University, Daejeon 34134, South Korea.
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A Comprehensive Evaluation of the Impact of Bovine Milk Containing Different Beta-Casein Profiles on Gut Health of Ageing Mice. Nutrients 2020; 12:nu12072147. [PMID: 32707687 PMCID: PMC7400800 DOI: 10.3390/nu12072147] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 07/15/2020] [Accepted: 07/17/2020] [Indexed: 12/12/2022] Open
Abstract
Ageing is often characterised by nutritional deficiencies and functional alterations of the digestive and immune system. The aim of the present study was to analyse the impact of consumption of conventional milk with A1/A2 beta-casein, compared to milk containing only the A2 beta-casein variant, characterised by a protein profile favouring gut health. Twenty-four ageing Balb-c mice (20 months old) were fed for 4 weeks, with either a control diet (CTRL), a diet supplemented with bovine milk containing A1/A2 beta-casein (A1A2) or a diet containing A2/A2 beta-casein (A2A2). Lymphocyte subpopulations, enzymatic activities, cytokine secretion, gut morphology and histopathological alterations were measured in different gut segments, while short-chain fatty acids (SCFAs) content and microbiota composition were evaluated in faecal samples. The A2A2 group showed higher content of faecal SCFAs (in particular, isobutyrate) of intestinal CD4+ and CD19+ lymphocytes in the intraepithelial compartment and improved villi tropism. The A1A2 group showed higher percentages of intestinal TCRγδ+ lymphocytes. Faecal microbiota identified Deferribacteriaceae and Desulfovibrionaceae as the most discriminant families for the A2A2 group, while Ruminococcaceae were associated to the A1A2 group. Taken together, these results suggest a positive role of milk, in particular when containing exclusively A2 beta-casein, on gut immunology and morphology of an ageing mice model.
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Protein and Peptides for Elderly Health. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2018; 112:265-308. [DOI: 10.1016/bs.apcsb.2018.03.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Abstract
The number of persons 60 years and older has increased 3-fold between 1950 and 2000. Aging alone does not greatly impact the gastrointestinal (GI) tract. Digestive dysfunction, including esophageal reflux, achalasia, dysphagia, dyspepsia, delayed gastric emptying, constipation, fecal incontinence, and fecal impaction, is a result of the highly prevalent comorbid conditions and the medications with which those conditions are treated. A multidisciplinary approach with the expertise of a geriatrician, gastroenterologist, neurologist, speech pathologist, and physical therapist ensures a comprehensive functional and neurological assessment of the older patient. Radiographic and endoscopic evaluation may be warranted in the evaluation of the symptomatic older patient with consideration given to the risks and benefits of the test being used. Treatment of the digestive dysfunction is aimed at improving health-related quality of life if cure cannot be achieved. Promotion of healthy aging, treatment of comorbid conditions, and avoidance of polypharmacy may prevent some of these digestive disorders. The age-related changes in GI motility, clinical presentation of GI dysmotility, and therapeutic principles in the symptomatic older patient are reviewed here.
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Austin K, Markovic MA, Brubaker PL. Current and potential therapeutic targets of glucagon-like peptide-2. Curr Opin Pharmacol 2016; 31:13-18. [PMID: 27580097 DOI: 10.1016/j.coph.2016.08.008] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Revised: 07/19/2016] [Accepted: 08/11/2016] [Indexed: 12/15/2022]
Abstract
Glucagon-like peptide-2 (GLP-2) is a gut hormone that promotes highly specific growth and function of the intestinal epithelium. Recent studies have begun to elucidate the complex mechanism of action of GLP-2, which is mediated indirectly through other intestinal factors. Although a long-acting GLP-2 analog has recently been approved for treatment of adult patients with short bowel syndrome, there remain numerous conditions characterized by intestinal insufficiency for which pre-clinical studies, as well as some limited clinical data, support further consideration of GLP-2 for expanded therapeutic use.
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Affiliation(s)
- Kaori Austin
- Department of Physiology, Rm 3366 Medical Sciences Building, University of Toronto, 1 King's College Circle, Toronto, ON M5S 1A8, Canada
| | - Melanie A Markovic
- Department of Physiology, Rm 3366 Medical Sciences Building, University of Toronto, 1 King's College Circle, Toronto, ON M5S 1A8, Canada
| | - Patricia L Brubaker
- Department of Physiology, Rm 3366 Medical Sciences Building, University of Toronto, 1 King's College Circle, Toronto, ON M5S 1A8, Canada; Department of Medicine, Rm 3366 Medical Sciences Building, University of Toronto, 1 King's College Circle, Toronto, ON M5S 1A8, Canada.
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11
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Costa DK, Huckestein BR, Edmunds LR, Petersen MC, Nasiri A, Butrico GM, Abulizi A, Harmon DB, Lu C, Mantell BS, Hartman DJ, Camporez JPG, O'Doherty RM, Cline GW, Shulman GI, Jurczak MJ. Reduced intestinal lipid absorption and body weight-independent improvements in insulin sensitivity in high-fat diet-fed Park2 knockout mice. Am J Physiol Endocrinol Metab 2016; 311:E105-16. [PMID: 27166280 PMCID: PMC4967148 DOI: 10.1152/ajpendo.00042.2016] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 05/06/2016] [Indexed: 12/21/2022]
Abstract
Mitochondrial dysfunction is associated with many human diseases and results from mismatch of damage and repair over the life of the organelle. PARK2 is a ubiquitin E3 ligase that regulates mitophagy, a repair mechanism that selectively degrades damaged mitochondria. Deletion of PARK2 in multiple in vivo models results in susceptibility to stress-induced mitochondrial and cellular dysfunction. Surprisingly, Park2 knockout (KO) mice are protected from nutritional stress and do not develop obesity, hepatic steatosis or insulin resistance when fed a high-fat diet (HFD). However, these phenomena are casually related and the physiological basis for this phenotype is unknown. We therefore undertook a series of acute HFD studies to more completely understand the physiology of Park2 KO during nutritional stress. We find that intestinal lipid absorption is impaired in Park2 KO mice as evidenced by increased fecal lipids and reduced plasma triglycerides after intragastric fat challenge. Park2 KO mice developed hepatic steatosis in response to intravenous lipid infusion as well as during incubation of primary hepatocytes with fatty acids, suggesting that hepatic protection from nutritional stress was secondary to changes in energy balance due to altered intestinal triglyceride absorption. Park2 KO mice showed reduced adiposity after 1-wk HFD, as well as improved hepatic and peripheral insulin sensitivity. These studies suggest that changes in intestinal lipid absorption may play a primary role in protection from nutritional stress in Park2 KO mice by preventing HFD-induced weight gain and highlight the need for tissue-specific models to address the role of PARK2 during metabolic stress.
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Affiliation(s)
- Diana K Costa
- Department of Medicine, Yale University School of Medicine, New Haven, Connecticut
| | - Brydie R Huckestein
- Department of Endocrinology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Lia R Edmunds
- Department of Endocrinology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Max C Petersen
- Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, Connecticut
| | - Ali Nasiri
- Department of Medicine, Yale University School of Medicine, New Haven, Connecticut
| | - Gina M Butrico
- Department of Medicine, Yale University School of Medicine, New Haven, Connecticut
| | - Abudukadier Abulizi
- Department of Medicine, Yale University School of Medicine, New Haven, Connecticut
| | - Daniel B Harmon
- Department of Endocrinology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Canying Lu
- Department of Endocrinology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Benjamin S Mantell
- Department of Endocrinology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Douglas J Hartman
- Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | | | - Robert M O'Doherty
- Department of Endocrinology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania; Center for Metabolic and Mitochondrial Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Gary W Cline
- Department of Medicine, Yale University School of Medicine, New Haven, Connecticut
| | - Gerald I Shulman
- Department of Medicine, Yale University School of Medicine, New Haven, Connecticut; Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, Connecticut; The Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, Connecticut; and
| | - Michael J Jurczak
- Department of Endocrinology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania; Center for Metabolic and Mitochondrial Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
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12
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Morphometric and biomechanical remodeling of the small intestine during aging in rats. J Biomech 2015; 48:4271-8. [DOI: 10.1016/j.jbiomech.2015.10.034] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 10/22/2015] [Accepted: 10/23/2015] [Indexed: 01/27/2023]
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13
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Milan AM, Cameron-Smith D. Digestion and Postprandial Metabolism in the Elderly. ADVANCES IN FOOD AND NUTRITION RESEARCH 2015; 76:79-124. [PMID: 26602572 DOI: 10.1016/bs.afnr.2015.09.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The elderly are an increasing segment of the population. Despite the rapid gains in medical knowledge and treatments, older adults are more likely to experience chronic illnesses that decrease quality of life and accelerate mortality. Nutrition is a key modifiable lifestyle factor which greatly impacts chronic disease risk. Yet despite the importance of nutrition, relatively little is known of the impact of advancing age on the gastrointestinal function, the digestive responses, and the post-meal metabolic adaptations that occur in response to ingested food. Knowledge of the age-related differences in digestion and metabolism in the elderly is essential to the development of appropriate nutritional recommendations for the maintenance of optimal health and prevention of disease.
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Affiliation(s)
- Amber M Milan
- Liggins Institute, University of Auckland, Auckland, New Zealand
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Beaufrère AM, Neveux N, Patureau Mirand P, Buffière C, Marceau G, Sapin V, Cynober L, Meydinal-Denis D. Long-term intermittent glutamine supplementation repairs intestinal damage (structure and functional mass) with advanced age: assessment with plasma citrulline in a rodent model. J Nutr Health Aging 2014; 18:814-9. [PMID: 25389959 DOI: 10.1007/s12603-014-0554-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVE Glutamine is the preferred fuel for the rat small intestine and promotes the growth of intestinal mucosa, especially in the event of gut injury. Quantitatively, glutamine is one important precursor for intestinal citrulline release. The aim of this study was to determine whether the effect of glutamine on the increase in intestinal villus height is correlated with an increase in both gut mass and citrulline plasma level in very old rats. METHODS We intermittently supplemented very old (27-mo) female rats with oral glutamine (20% of diet protein). Intestinal histomorphometric analysis of the small bowel was performed. Amino acids, in particular citrulline, were measured in the plasma, liver and jejunum. Markers of renal (creatinine, urea) and liver (alanine aminotransferase [ALT]) and aspartate aminotransferase (AST) functions were measured to evaluate renal and liver functions in relation to aging and to glutamine supplementation. Liver glutathione was also determined to evaluate cellular redox state. RESULTS Glutamine supplementation maintains the body weight of very old rats, not by limiting sarcopenia but rather by increasing the organ mass of the splanchnic area. Total intestine mass was significantly higher in glutamine-supplemented rats than in controls (15%). Measurement of villus height and crypt depth demonstrated that the difference between villus and crypt was significantly improved in glutamine pre-treated rats compared to controls (~ 11%). Plasma citrulline also increased by 15% in glutamine-supplemented rats compared to controls. CONCLUSION Citrulline appears as a biomarker of enterocyte mass in villous atrophy associated with advanced age. Non-invasive measurement of this metabolite may be useful in following the state of the gastrointestinal tract in very old people, whose numbers are increasing worldwide and the care of whom is a major public health issue. The gut may contribute to the malnutrition caused by malabsorption frequently observed in the elderly.
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Affiliation(s)
- A M Beaufrère
- Dominique Meynial-Denis (PhD), Human Nutrition Unit, INRA and Human Nutrition Research Center, Theix 63122 - St Genes Champanelle, France. Phone: +33 (0)4 73 62 43 13; Fax: +33 (0)4 73 62 47 55; E-mail address:
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15
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Abstract
OPINION STATEMENT The careful review of drug-drug interactions is vital to the safe prescribing of medications for chronic medical conditions. The elderly population suffers from multiple medical problems, and polypharmacy leads to further morbidity in this vulnerable group of patients. We discuss gastrointestinal conditions such as GERD, peptic ulcer disease, gastroparesis, diarrhea, constipation, irritable bowel syndrome, inflammatory bowel disease, chronic liver disease and the commonly used medications in these conditions. Treatment options must be individualized and tailored to accommodate the underlying pharmacokinetics and known drug-drug interactions. The indication for the use of a therapeutic agent in the elderly and the duration of use must be frequently readdressed to help prevent polypharmacy and adverse drug reactions. Medications should be started at a low dose with careful titration to achieve a clinical response to prevent toxicity. The aim of this article is to increase awareness of important drug-drug interactions of commonly prescribed gastrointestinal medications in the elderly.
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Saffrey MJ. Aging of the mammalian gastrointestinal tract: a complex organ system. AGE (DORDRECHT, NETHERLANDS) 2014; 36:9603. [PMID: 24352567 PMCID: PMC4082571 DOI: 10.1007/s11357-013-9603-2] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Accepted: 11/25/2013] [Indexed: 05/23/2023]
Abstract
Gastrointestinal disorders are a major cause of morbidity in the elderly population. The gastrointestinal tract is the most complex organ system; its diverse cells perform a range of functions essential to life, not only secretion, digestion, absorption and excretion, but also, very importantly, defence. The gastrointestinal tract acts not only as a barrier to harmful materials and pathogens but also contains the vast number of beneficial bacterial populations that make up the microbiota. Communication between the cells of the gastrointestinal tract and the central nervous and endocrine systems modifies behaviour; the organisms of the microbiota also contribute to this brain-gut-enteric microbiota axis. Age-related physiological changes in the gut are not only common, but also variable, and likely to be influenced by external factors as well as intrinsic aging of the cells involved. The cellular and molecular changes exhibited by the aging gut cells also vary. Aging intestinal smooth muscle cells exhibit a number of changes in the signalling pathways that regulate contraction. There is some evidence for age-associated degeneration of neurons and glia of the enteric nervous system, although enteric neuronal losses are likely not to be nearly as extensive as previously believed. Aging enteric neurons have been shown to exhibit a senescence-associated phenotype. Epithelial stem cells exhibit increased mitochondrial mutation in aging that affects their progeny in the mucosal epithelium. Changes to the microbiota and intestinal immune system during aging are likely to contribute to wider aging of the organism and are increasingly important areas of analysis. How changes of the different cell types of the gut during aging affect the numerous cellular interactions that are essential for normal gut functions will be important areas for future aging research.
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Affiliation(s)
- M Jill Saffrey
- Department of Life Health and Chemical Sciences, Biomedical Research Network, The Open University, Milton Keynes, MK7 6AA, UK,
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17
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Tu CP, Tsai CH, Tsai CC, Huang TS, Cheng SP, Liu TP. Postoperative Ileus in the Elderly. INT J GERONTOL 2014. [DOI: 10.1016/j.ijge.2013.08.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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18
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Patel BA, Patel N, Fidalgo S, Wang C, Ranson RN, Saffrey MJ, Yeoman MS. Impaired colonic motility and reduction in tachykinin signalling in the aged mouse. Exp Gerontol 2014; 53:24-30. [PMID: 24560671 DOI: 10.1016/j.exger.2014.02.007] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2013] [Revised: 02/05/2014] [Accepted: 02/10/2014] [Indexed: 02/07/2023]
Abstract
Ageing is associated with an increased incidence of constipation in humans. The contribution that the ageing process makes to this condition is unclear. The aim of this study was to determine the effects of age on faecal output and colonic motility in male C57BL/6J mice and to determine the role that altered tachykinin signalling plays in this process. Total faecal output recorded over a 24h period decreased with age due to a reduction in the number of pellets produced and their water content. These changes occurred in the absence of any significant change in food and water intake. There was an increase in the amount of faecal matter stored in the isolated colon with age which caused a proportional increase in colonic length. Analysis of colonic motility using an artificial pellet demonstrated that pellets moved in a stepwise fashion through the colon. There was an age-related increase in pellet transit time due to decreases in the step distance, velocity, and frequency of stepwise movements. These changes were reversed using the neurokinin 2 (NK2) receptor agonist neurokinin A. Addition of the NK2receptor antagonist GR159897 significantly increased transit time in the young animals by decreasing step distance, velocity and frequency, but was without effect in the aged colon. In summary, the ageing C57BL/6J mouse shows an impaired motility phenotype. These effects appear, at least in part, to be due to an attenuation of tachykinin signalling via NK2 receptors.
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Affiliation(s)
- Bhavik Anil Patel
- School of Pharmacy and Biomolecular Sciences, Huxley Building, University of Brighton, Lewes Road, Brighton BN2 4GJ, UK
| | - Nikkita Patel
- School of Pharmacy and Biomolecular Sciences, Huxley Building, University of Brighton, Lewes Road, Brighton BN2 4GJ, UK
| | - Sara Fidalgo
- School of Pharmacy and Biomolecular Sciences, Huxley Building, University of Brighton, Lewes Road, Brighton BN2 4GJ, UK
| | - Chunfang Wang
- Department of Life, Health and Chemical Sciences, Biomedical Research Network, Open University, Walton Hall, Milton Keynes MK7 6AA, UK
| | - Richard N Ranson
- Faculty of Health and Life Sciences, Northumbria University, Ellison Building, Newcastle upon Tyne NE1 8ST, UK
| | - M Jill Saffrey
- Department of Life, Health and Chemical Sciences, Biomedical Research Network, Open University, Walton Hall, Milton Keynes MK7 6AA, UK
| | - Mark S Yeoman
- School of Pharmacy and Biomolecular Sciences, Huxley Building, University of Brighton, Lewes Road, Brighton BN2 4GJ, UK.
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19
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Mocchegiani E, Romeo J, Malavolta M, Costarelli L, Giacconi R, Diaz LE, Marcos A. Zinc: dietary intake and impact of supplementation on immune function in elderly. AGE (DORDRECHT, NETHERLANDS) 2013; 35:839-60. [PMID: 22222917 PMCID: PMC3636409 DOI: 10.1007/s11357-011-9377-3] [Citation(s) in RCA: 102] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2011] [Accepted: 12/21/2011] [Indexed: 05/07/2023]
Abstract
The diet in the elderly does not provide a sufficient level of nutrients needed to maintain an adequate healthy status leading to micronutrient deficiencies and impaired immune response with subsequent development of degenerative diseases. Nutrient "zinc" is a relevant micronutrient involved in maintaining a good integrity of many body homeostatic mechanisms, including immune efficiency, owing to its requirement for the biological activity of many enzymes, proteins and for cellular proliferation and genomic stability. Old people aged 60-65 years and older have zinc intakes below 50% of the recommended daily allowance on a given day. Many causes can be involved: among them, altered intestinal absorption, inadequate mastication, psychosocial factors, drugs interactions, altered subcellular processes (zinc transporters (Zip and ZnT family), metallothioneins, divalent metal transporter-1). Zinc supplementation may remodel the immune alterations in elderly leading to healthy ageing. Several zinc trials have been carried out with contradictory data, perhaps due to incorrect choice of an effective zinc supplementation in old subjects showing subsequent zinc toxic effects on immunity. Old subjects with specific IL-6 polymorphism (GG allele carriers; named C-) are more prone for zinc supplementation than the entire old population, in whom correct dietary habits with foods containing zinc (Mediterranean diet) may be sufficient in restoring zinc deficiency and impaired immune response. We summarise the main causes of low zinc dietary intake in elderly reporting an update on the impact of zinc supplementation upon the immune response also on the basis of individual IL-6 polymorphism.
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Affiliation(s)
- Eugenio Mocchegiani
- Ctr. Nutrition and Ageing, Italian National Research Centres on Ageing (INRCA), Via Birarelli 8, 60121, Ancona, Italy.
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20
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Stehle JR, Leng X, Kitzman DW, Nicklas BJ, Kritchevsky SB, High KP. Lipopolysaccharide-binding protein, a surrogate marker of microbial translocation, is associated with physical function in healthy older adults. J Gerontol A Biol Sci Med Sci 2012; 67:1212-8. [PMID: 22960476 DOI: 10.1093/gerona/gls178] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
BACKGROUND Physical function declines, and markers of inflammation increase with advancing age, even in healthy persons. Microbial translocation (MT) is the systemic exposure to mucosal surface microbes/microbial products without overt bacteremia and has been described in a number of pathologic conditions. We hypothesized that markers of MT, soluble CD14 (sCD14) and lipopolysaccharide (LPS) binding protein (LBP), may be a source of chronic inflammation in older persons and be associated with poorer physical function. METHODS We assessed cross-sectional relationships among two plasma biomarkers of MT (sCD14 and LBP), physical function (hand grip strength, short physical performance battery [SPPB], gait speed, walking distance, and disability questionnaire), and biomarkers of inflammation (C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), TNF-α soluble receptor 1 [TNFsR1]) in 59 older (60-89 years), healthy (no evidence of acute or chronic illness) men and women. RESULTS LBP was inversely correlated with SPPB score and grip strength (p = .02 and p < .01, respectively) and positively correlated with CRP (p = 0.04) after adjusting for age, gender, and body mass index. sCD14 correlated with IL-6 (p = .01), TNF-α (p = .05), and TNFsR1 (p < .0001). Furthermore, the correlations between LBP and SPPB and grip strength remained significant after adjusting for each inflammatory biomarker. CONCLUSIONS In healthy older individuals, LBP, a surrogate marker of MT, is associated with worse physical function and inflammation. Additional study is needed to determine whether MT is a marker for or a cause of inflammation and the associated functional impairments.
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Affiliation(s)
- John R Stehle
- Section on Gerontology and Geriatric Medicine, Department of Internal Medicine, Wake Forest School of Medicine, Medical Center Boulevard, Winston-Salem, NC 27157, USA.
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Fox RG, Magness S, Kujoth GC, Prolla TA, Maeda N. Mitochondrial DNA polymerase editing mutation, PolgD257A, disturbs stem-progenitor cell cycling in the small intestine and restricts excess fat absorption. Am J Physiol Gastrointest Liver Physiol 2012; 302:G914-24. [PMID: 22345551 PMCID: PMC3362078 DOI: 10.1152/ajpgi.00402.2011] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Changes in intestinal absorption of nutrients are important aspects of the aging process. To address this issue, we investigated the impact of accelerated mitochondrial DNA mutations on the stem/progenitor cells in the crypts of Lieberkühn in mice homozygous for a mitochondrial DNA polymerase gamma mutation, Polg(D257A), that exhibit accelerated aging phenotype. As early as 3-7 mo of age, the small intestine was significantly enlarged in the PolgD257A mice. The crypts of the PolgD257A mice contained 20% more cells than those of their wild-type littermates and exhibited a 10-fold increase in cellular apoptosis primarily in the stem/progenitor cell zones. Actively dividing cells were proportionally increased, yet a significantly smaller proportion of cells was in the S phase of the cell cycle. Stem cell-derived organoids from PolgD257A mice failed to develop fully in culture and exhibited fewer crypt units, indicating an impact of the mutation on the intestinal epithelial stem/progenitor cell maintenance. In addition, epithelial cell migration along the crypt-villus axis was slowed and less organized, and the ATP content in the villi was significantly reduced. On a high-fat, high-carbohydrate diet, PolgD257A mice showed significantly restricted absorption of excess lipids accompanied by an increase in fecal steatocrits. We conclude that the PolgD257A mutation causes cell cycle dysregulation in the crypts leading to the age-associated changes in the morphology of the small intestine and contributes to the restricted absorption of dietary lipids.
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Affiliation(s)
- Raymond G. Fox
- 1Curriculum in Genetics and Molecular Biology, ,2Department of Pathology and Laboratory Medicine,
| | - Scott Magness
- 3Department of Medicine, Division of Gastroenterology and Hepatology, University of North Carolina, Chapel Hill, North Carolina; and
| | - Gregory C. Kujoth
- Departments of 4Genetics and Medical Genetics and ,5Neurological Surgery, University of Wisconsin, Madison, Wisconsin
| | | | - Nobuyo Maeda
- 1Curriculum in Genetics and Molecular Biology, ,2Department of Pathology and Laboratory Medicine,
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Parmar L, Fidalgo S, Yeoman MS, Patel BA. Chromatographic analysis of age-related changes in mucosal serotonin transmission in the murine distal ileum. Chem Cent J 2012; 6:31. [PMID: 22494644 PMCID: PMC3483693 DOI: 10.1186/1752-153x-6-31] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2011] [Accepted: 02/27/2012] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND In the upper bowel, alterations in motility and absorption of key nutrients have been observed as part of the normal ageing process. Serotonin (5-HT) is a key signalling molecule in the gastrointestinal tract and is known to influence motility, however little is known of how the ageing process alters 5-HT signalling processes in the bowel. RESULTS An isocratic chromatographic method was able to detect all 5-HT precursors and metabolites. Using extracellular and intracellular sampling approaches, we were able to monitor all key parameters associated with the transmission process. There was no alteration in the levels of tryptophan and 5-HTP between 3 and 18 month old animals. There was a significant increase in the ratio of 5-HT:5-HTP and an increase in intracellular 5-HT between 3 and 18 month old animals suggesting an increase in 5-HT synthesis. There was also a significant increase in extracellular 5-HT with age, suggesting increased 5-HT release. There was an age-related decrease in the ratio of intracellular 5-HIAA:extracellular 5-HT, whilst the amount of 5-HIAA did not change with age. In the presence of an increase in extracellular 5-HT, the lack of an age-related change in 5-HIAA is suggestive of a decrease in re-uptake via the serotonin transporter (SERT). CONCLUSIONS We have used intracellular and extracellular sampling to provide more insight into alterations in the neurotransmission process of 5-HT during normal ageing. We observed elevated 5-HT synthesis and release and a possible decrease in the activity of SERT. Taken together these changes lead to increased 5-HT availability and may alter motility function and could lead to the changes in adsorption observed in the elderly.
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Affiliation(s)
- Leena Parmar
- Centre for Biomedical and Health Sciences Research, University of Brighton, Brighton, BN2 4GJ, UK.
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23
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Phillips RJ, Powley TL. Macrophages associated with the intrinsic and extrinsic autonomic innervation of the rat gastrointestinal tract. Auton Neurosci 2012; 169:12-27. [PMID: 22436622 DOI: 10.1016/j.autneu.2012.02.004] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2012] [Revised: 02/22/2012] [Accepted: 02/23/2012] [Indexed: 12/28/2022]
Abstract
Interactions between macrophages and the autonomic innervation of gastrointestinal (GI) tract smooth muscle have received little experimental attention. To better understand this relationship, immunohistochemistry was performed on GI whole mounts from rats at three ages. The phenotypes, morphologies, and distributions of gut macrophages are consistent with the cells performing extensive housekeeping functions in the smooth muscle layers. Specifically, a dense population of macrophages was located throughout the muscle wall where they were distributed among the muscle fibers and along the vasculature. Macrophages were also associated with ganglia and connectives of the myenteric plexus and with the sympathetic innervation. Additionally, these cells were in tight registration with the dendrites and axons of the myenteric neurons as well as the varicosities along the length of the sympathetic axons, suggestive of a contribution by the macrophages to the homeostasis of both synapses and contacts between the various elements of the enteric circuitry. Similarly, macrophages were involved in the presumed elimination of neuropathies as indicated by their association with dystrophic neurons and neurites which are located throughout the myenteric plexus and smooth muscle wall of aged rats. Importantly, the patterns of macrophage-neuron interactions in the gut paralleled the much more extensively characterized interactions of macrophages (i.e., microglia) and neurons in the CNS. The present observations in the PNS as well as extrapolations from homologous microglia in the CNS suggest that GI macrophages play significant roles in maintaining the nervous system of the gut in the face of wear and tear, disease, and aging.
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Affiliation(s)
- Robert J Phillips
- Department of Psychological Sciences, Purdue University, West Lafayette, Indiana 47907-2081, USA
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Abstract
Celiac disease now affects about one person in a hundred in Europe and North America. In this review, we consider a number of important and exciting recent developments, such as clinical associations, HLA-DQ2 and HLA-DQ8 predispositions, the concept of potential celiac disease, the use of new imaging/endoscopy techniques, and the development of refractory disease. This review will be of use to all internists, pediatricians and gastroenterologists.
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Freeman HJ, Chopra A, Clandinin MT, Thomson ABR. Recent advances in celiac disease. World J Gastroenterol 2011; 17:2259-72. [PMID: 21633592 PMCID: PMC3098394 DOI: 10.3748/wjg.v17.i18.2259] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2011] [Revised: 02/12/2011] [Accepted: 02/19/2011] [Indexed: 02/06/2023] Open
Abstract
Celiac disease now affects about one person in a hundred in Europe and North America. In this review, we consider a number of important and exciting recent developments, such as clinical associations, HLA-DQ2 and HLA-DQ8 predispositions, the concept of potential celiac disease, the use of new imaging/endoscopy techniques, and the development of refractory disease. This review will be of use to all internists, pediatricians and gastroenterologists.
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