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Madsen K, Cornish A, Soper P, McKaigney C, Jijon H, Yachimec C, Doyle J, Jewell L, De Simone C. Probiotic bacteria enhance murine and human intestinal epithelial barrier function. Gastroenterology 2001; 121:580-91. [PMID: 11522742 DOI: 10.1053/gast.2001.27224] [Citation(s) in RCA: 741] [Impact Index Per Article: 30.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND & AIMS The probiotic compound, VSL#3, is efficacious as maintenance therapy in pouchitis and ulcerative colitis. The aim of this study was to determine the efficacy of VSL#3 as a primary therapy in the treatment of colitis in the interleukin (IL)-10 gene-deficient mouse. Mechanisms of action of VSL#3 were investigated in T(84) monolayers. METHODS IL-10 gene-deficient and control mice received 2.8 x 10(8) colony-forming units per day of VSL#3 for 4 weeks. Colons were removed and analyzed for cytokine production, epithelial barrier function, and inflammation. VSL#3 or conditioned media was applied directly to T(84) monolayers. RESULTS Treatment of IL-10 gene-deficient mice with VSL#3 resulted in normalization of colonic physiologic function and barrier integrity in conjunction with a reduction in mucosal secretion of tumor necrosis factor alpha and interferon gamma and an improvement in histologic disease. In vitro studies showed that epithelial barrier function and resistance to Salmonella invasion could be enhanced by exposure to a proteinaceous soluble factor secreted by the bacteria found in the VSL#3 compound. CONCLUSIONS Oral administration of VSL#3 was effective as primary therapy in IL-10 gene-deficient mice, and had a direct effect on epithelial barrier function.
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Madsen KL, Doyle JS, Jewell LD, Tavernini MM, Fedorak RN. Lactobacillus species prevents colitis in interleukin 10 gene-deficient mice. Gastroenterology 1999; 116:1107-14. [PMID: 10220502 DOI: 10.1016/s0016-5085(99)70013-2] [Citation(s) in RCA: 569] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND & AIMS Intestinal luminal microflora, or their products, are likely an important initiating factor in the pathogenesis of inflammatory bowel disease. The aim of this study was to determine the role of colonic aerobic luminal bacteria and Lactobacillus species in the development of colitis in interleukin (IL)-10 gene-deficient mice. METHODS Intestine from 2-16-week-old mice was scored histologically and cultured for bacteria. Lactobacillus sp. repopulation of the colonic lumen was achieved via daily rectal delivery of Lactobacillus reuteri or oral lactulose therapy. RESULTS At 2 weeks of age, IL-10 gene-deficient mice showed no colonic injury but did display abnormal colonic bacterial colonization with increased colonic mucosal aerobic adherent and translocated bacteria in conjunction with reduced Lactobacillus sp. levels. In association with the abnormal colonic bacterial colonization, colitis developed by 4 weeks of age. Restoring Lactobacillus sp. to normal levels reduced levels of colonic mucosal adherent and translocated bacteria and attenuated the development of the colitis. CONCLUSIONS In the neonatal period, IL-10 gene-deficient mice have decreased levels of colonic Lactobacillus sp. and an increase in colonic mucosal adherent and translocated bacteria. Normalizing Lactobacillus sp. levels reduced colonic mucosal adherent and translocated bacteria and prevented colitis.
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Knudsen LB, Nielsen PF, Huusfeldt PO, Johansen NL, Madsen K, Pedersen FZ, Thøgersen H, Wilken M, Agersø H. Potent derivatives of glucagon-like peptide-1 with pharmacokinetic properties suitable for once daily administration. J Med Chem 2000; 43:1664-9. [PMID: 10794683 DOI: 10.1021/jm9909645] [Citation(s) in RCA: 524] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
A series of very potent derivatives of the 30-amino acid peptide hormone glucagon-like peptide-1 (GLP-1) is described. The compounds were all derivatized with fatty acids in order to protract their action by facilitating binding to serum albumin. GLP-1 had a potency (EC(50)) of 55 pM for the cloned human GLP-1 receptor. Many of the compounds had similar or even higher potencies, despite quite large substituents. All compounds derivatized with fatty acids equal to or longer than 12 carbon atoms were very protracted compared to GLP-1 and thus seem suitable for once daily administration to type 2 diabetic patients. A structure-activity relationship was obtained. GLP-1 could be derivatized with linear fatty acids up to the length of 16 carbon atoms, sometimes longer, almost anywhere in the C-terminal part without considerable loss of potency. Derivatization with two fatty acid substituents led to a considerable loss of potency. A structure-activity relationship on derivatization of specific amino acids generally was obtained. It was found that the longer the fatty acid, the more potency was lost. Simultaneous modification of the N-terminus (in order to obtain better metabolic stability) interfered with fatty acid derivatization and led to loss of potency.
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Shiraishi F, Curtis LM, Truong L, Poss K, Visner GA, Madsen K, Nick HS, Agarwal A. Heme oxygenase-1 gene ablation or expression modulates cisplatin-induced renal tubular apoptosis. Am J Physiol Renal Physiol 2000; 278:F726-36. [PMID: 10807584 DOI: 10.1152/ajprenal.2000.278.5.f726] [Citation(s) in RCA: 254] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Heme oxygenase-1 (HO-1) is a 32-kDa microsomal enzyme that catalyzes the conversion of heme to biliverdin, releasing iron and carbon monoxide. Induction of HO-1 occurs as a protective response in cells/tissues exposed to a wide variety of oxidant stimuli. The chemotherapeutic effects of cis-diamminedichloroplatinum(II) (cisplatin), a commonly used anticancer drug, are limited by significant nephrotoxicity, which is characterized by varying degrees of renal tubular apoptosis and necrosis. The purpose of this study was to evaluate the functional significance of HO-1 expression in cisplatin-induced renal injury. Our studies demonstrate that transgenic mice deficient in HO-1 (-/-), develop more severe renal failure and have significantly greater renal injury compared with wild-type (+/+) mice treated with cisplatin. In vitro studies in human renal proximal tubule cells demonstrate that hemin, an inducer of HO-1, significantly attenuated cisplatin-induced apoptosis and necrosis, whereas inhibition of HO-1 enzyme activity reversed the cytoprotective effect. Overexpression of HO-1 resulted in a significant reduction in cisplatin-induced cytotoxicity. These studies provide a basis for future studies using targeted gene expression of HO-1 as a therapeutic and preventive modality in high-risk settings of acute renal failure.
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Arrieta MC, Madsen K, Doyle J, Meddings J. Reducing small intestinal permeability attenuates colitis in the IL10 gene-deficient mouse. Gut 2008; 58:41-8. [PMID: 18829978 PMCID: PMC2597688 DOI: 10.1136/gut.2008.150888] [Citation(s) in RCA: 235] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Defects in the small intestinal epithelial barrier have been associated with inflammatory bowel disease but their role in the causation of disease is still a matter of debate. In some models of disease increased permeability appears to be a very early event. The interleukin 10 (IL10) gene-deficient mouse spontaneously develops colitis after 12 weeks of age. These mice have been shown to have increased small intestinal permeability that appears early in life. Furthermore, the development of colitis is dependent upon luminal agents, as animals do not develop disease if raised under germ-free conditions. AIMS To determine if the elevated small bowel permeability can be prevented, and if by doing so colonic disease is prevented or attenuated. METHODS IL10 gene-deficient (IL10(-)/(-)) mice) were treated with AT-1001 (a zonulin peptide inhibitor), a small peptide previously demonstrated to reduce small intestinal permeability. Small intestinal permeability was measured, in vivo, weekly from 4 to 17 weeks of age. Colonic disease was assessed at 8 weeks in Ussing chambers, and at 17 weeks of age inflammatory cytokines and myeloperoxidase were measured in the colon. Colonic permeability and histology were also endpoints. RESULTS Treated animals showed a marked reduction in small intestinal permeability. Average area under the lactulose/mannitol time curve: 5.36 (SE 0.08) in controls vs 3.97 (SE 0.07) in the high-dose AT-1001 group, p<0.05. At 8 weeks of age there was a significant reduction of colonic mucosal permeability and increased electrical resistance. By 17 weeks of age, secretion of tumour necrosis factor alpha (TNFalpha) from a colonic explant was significantly lower in the treated group (25.33 (SE 4.30) pg/mg vs 106.93 (SE 17.51) pg/ml in controls, p<0.01). All other markers also demonstrated a clear reduction of colitis in the treated animals. Additional experiments were performed which demonstrated that AT-1001 was functionally active only in the small intestine. CONCLUSIONS This work suggests that increased intestinal permeability may be an important aetiological event in the development of colitis in IL10(-)/(-) mice.
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Deacon CF, Knudsen LB, Madsen K, Wiberg FC, Jacobsen O, Holst JJ. Dipeptidyl peptidase IV resistant analogues of glucagon-like peptide-1 which have extended metabolic stability and improved biological activity. Diabetologia 1998; 41:271-8. [PMID: 9541166 DOI: 10.1007/s001250050903] [Citation(s) in RCA: 222] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Glucagon-like peptide 1 (GLP-1) has great potential in diabetes therapy due to its glucose-dependent stimulation of insulin secretion, but this is limited by its rapid degradation, primarily by dipeptidyl peptidase IV. Four analogues, N-terminally substituted with threonine, glycine, serine or alpha-aminoisobutyric acid, were synthesised and tested for metabolic stability. All were more resistant to dipeptidyl peptidase IV in porcine plasma in vitro, ranging from a t1/2 of 159 min (Gly8 analogue) to undetectable degradation after 6 h (Aib8 analogue; t1/2 for GLP-1 (7-36) amide, 28 min). During i. v. infusion in anaesthetised pigs, over 50% of each analogue remained undegraded compared to 22.7 % for GLP-1 (7-36) amide. In vivo, analogues had longer N-terminal t1/2 (intact peptides: means, 3.3-3.9 min) than GLP-1 (7-36) amide (0.9 min; p < 0.01), but these did not exceed the C-terminal t1/2 (intact plus metabolite: analogues, 3.5-4.4 min; GLP-1 (7-36) amide, 4.1 min). Analogues were assessed for receptor binding using a cell line expressing the cloned receptor, and for ability to stimulate insulin or inhibit glucagon secretion from the isolated perfused porcine pancreas. All bound to the receptor, but only the Aib8 and Gly8 analogues had similar affinities to GLP-1 (7-36) amide (IC50; Aib8=0.45 nmol/l; Gly8=2.8 nmol/l; GLP-1 (7-36) amide=0.78 nmol/l). All analogues were active in the isolated pancreas, with the potency order reflecting receptor affinities (Aib8 > Gly8 > Ser8 > Thr8). N-terminal modification of GLP-1 confers resistance to dipeptidyl peptidase IV degradation. Such analogues are biologically active and have prolonged metabolic stability in vivo, which, if associated with greater potency and duration of action, may help to realise the potential of GLP-1 in diabetes therapy.
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Madsen KL, Malfair D, Gray D, Doyle JS, Jewell LD, Fedorak RN. Interleukin-10 gene-deficient mice develop a primary intestinal permeability defect in response to enteric microflora. Inflamm Bowel Dis 1999; 5:262-70. [PMID: 10579119 DOI: 10.1097/00054725-199911000-00004] [Citation(s) in RCA: 217] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The normal intestinal epithelium provides a barrier relatively impermeable to luminal constituents. However, patients with inflammatory bowel disease experience enhanced intestinal permeability that correlates with the degree of injury. IL-10 gene-deficient mice were studied to determine whether increased intestinal permeability occurs as a primary defect before the onset of mucosal inflammation or is secondary to mucosal injury. At 2 weeks of age, IL-10 gene-deficient mice show an increase in ileal and colonic permeability in the absence of any histological injury. This primary permeability defect is associated with increased mucosal secretion of interferon-gamma and tumor necrosis factor-alpha, and does not involve an increase in nitric oxide synthase activity. Colonic permeability remains elevated as inflammation progresses, while ileal permeability normalizes by 6 weeks of age. IL-10 gene-deficient mice raised under germ-free conditions have no inflammation, and demonstrate normal permeability and cytokine levels. This data suggests that the intestinal permeability defect in IL-10 gene-deficient mice occurs due to a dysregulated immune response to normal enteric microflora and, furthermore, this permeability defect exists prior to the development of mucosal inflammation.
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Tschöp M, Castañeda TR, Joost HG, Thöne-Reineke C, Ortmann S, Klaus S, Hagan MM, Chandler PC, Oswald KD, Benoit SC, Seeley RJ, Kinzig KP, Moran TH, Beck-sickinger AG, Koglin N, Rodgers RJ, Blundell JE, Ishii Y, Beattie AH, Holch P, Allison DB, Raun K, Madsen K, Wulff BS, Stidsen CE, Birringer M, Kreuzer OJ, Schindler M, Arndt K, Rudolf K, Mark M, Deng XY, Whitcomb DC, Halem H, Taylor J, Dong J, Datta R, Culler M, Craney S, Flora D, Smiley D, Heiman ML, Withcomb DC. Physiology: does gut hormone PYY3-36 decrease food intake in rodents? Nature 2004; 430:1 p following 165; discussion 2 p following 165. [PMID: 15243972 DOI: 10.1038/nature02665] [Citation(s) in RCA: 187] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Batterham et al. report that the gut peptide hormone PYY3-36 decreases food intake and body-weight gain in rodents, a discovery that has been heralded as potentially offering a new therapy for obesity. However, we have been unable to replicate their results. Although the reasons for this discrepancy remain undetermined, an effective anti-obesity drug ultimately must produce its effects across a range of situations. The fact that the findings of Batterham et al. cannot easily be replicated calls into question the potential value of an anti-obesity approach that is based on administration of PYY3-36.
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Madsen KL, Doyle JS, Tavernini MM, Jewell LD, Rennie RP, Fedorak RN. Antibiotic therapy attenuates colitis in interleukin 10 gene-deficient mice. Gastroenterology 2000; 118:1094-105. [PMID: 10833484 DOI: 10.1016/s0016-5085(00)70362-3] [Citation(s) in RCA: 183] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
BACKGROUND & AIMS Interleukin (IL)-10 gene-deficient mice, raised under germfree conditions, do not develop colitis, implying a role for bacteria. This study mapped the appearance of luminal colonic bacteria and, using antibiotic treatment, determined their association with colitis in IL-10 gene-deficient mice. METHODS Mice were treated with ciprofloxacin or with neomycin and metronidazole. The intestine was harvested for histological scoring and bacterial assessment. RESULTS At 2 weeks of age, before the development of colitis, IL-10 gene-deficient mice demonstrated an earlier appearance of Streptococcus and Clostridium sp., and had a greater proportion (P < 0.01) of bacteria adherent to the colonic mucosa. This pattern of increased adherent bacteria persisted for the 12 weeks of study. Treatment of mice before the onset of colonic inflammation, with either antibiotic regime, reduced mucosal adherent bacteria and prevented colitis (P < 0.01). In contrast, treatment of established colitis with neomycin and metronidazole did not reduce adherent bacterial levels, yet was more efficacious (P < 0.05) in treating established colitis than ciprofloxacin, which did reduce adherent colonic bacteria. CONCLUSIONS In the IL-10 gene-deficient mouse model, the appearance and number of mucosal adherent colonic bacteria are altered before the onset of colitis. Antibiotics both prevent and treat the colitis through correction of this primary bacterial alteration.
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Bangsbo J, Madsen K, Kiens B, Richter EA. Effect of muscle acidity on muscle metabolism and fatigue during intense exercise in man. J Physiol 1996; 495 ( Pt 2):587-96. [PMID: 8887768 PMCID: PMC1160816 DOI: 10.1113/jphysiol.1996.sp021618] [Citation(s) in RCA: 149] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
1. The aim of this study was to examine the effect of muscle pH on muscle metabolism and development of fatigue during intense exercise. 2. Seven subjects performed intense exhaustive leg exercise on two occasions: with and without preceding intense intermittent arm exercise leading to high or moderate (control) blood lactate concentrations (HL and C, respectively). Prior to and immediately after each exercise bout, a muscle biopsy was taken from m. vastus lateralis of the active leg. Leg blood flow was measured and femoral arterial and venous blood samples were collected before and frequently during the exhaustive exercises. 3. The duration of the exercise was shorter in HL than in C (3.46 +/- 0.28 vs. 4.67 +/- 0.55 min; means +/- S.E.M.; P < 0.05). Before exercise muscle pH was the same in C and HL (7.17 vs. 7.10), but at the end of exercise muscle pH was lower in HL than in C (6.82 vs. 6.65; P < 0.05). The release of potassium during exercise was higher (P < 0.05) in HL compared with C, but the arterial and femoral venous plasma potassium concentrations were the same at exhaustion in HL and C. 4. Muscle lactate concentration was higher in HL compared with C (3.7 +/- 0.4 vs. 1.6 +/- 0.2 mmol (kg wet weight)-1; P < 0.05), but the same at exhaustion (26.5 +/- 2.7 vs. 25.4 +/- 2.4 mmol (kg wet weight)-1). Total release of lactate in HL was lower than in C (18.7 +/- 4.5 vs. 50.4 +/- 11.0 mmol; P < 0.05), but rate of lactate production was not different (9.0 +/- 1.0 vs. 10.2 +/- 1.3 mmol (kg wet weight)-1 min-1). The rate of muscle glycogen breakdown was the same in C and HL (8.1 +/- 1.2 vs. 8.2 +/- 1.0 mmol (kg wet weight)-1 min-1). 5. The present data suggest that elevated muscle acidity does not reduce muscle glycogenolysis/glycolysis and is not the only cause of fatigue during intense exercise in man. Instead, accumulation of potassium in muscle interstitium may be an important factor in the development of fatigue.
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Madsen KL, Lewis SA, Tavernini MM, Hibbard J, Fedorak RN. Interleukin 10 prevents cytokine-induced disruption of T84 monolayer barrier integrity and limits chloride secretion. Gastroenterology 1997; 113:151-9. [PMID: 9207273 DOI: 10.1016/s0016-5085(97)70090-8] [Citation(s) in RCA: 122] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND & AIMS The proinflammatory cytokine interferon gamma (IFN-gamma) disrupts epithelial barrier integrity and attenuates secretagogue-induced chloride secretion. This study tested the efficacy of the anti-inflammatory cytokine interleukin 10 (IL-10) in maintaining epithelial barrier and chloride secretory function in the presence of IFN-gamma. METHODS T84 epithelial cell monolayers were treated with IL-10, IFN-gamma, or IFN-gamma plus IL-10. Monolayer barrier integrity was assessed by measurements of electrical conductance, unidirectional mannitol and inulin fluxes, and tight junctional charge selectivity in Ussing chambers. Short-circuit current (Isc) was measured in response to carbachol and forskolin stimulation. RESULTS IL-10 attenuated the IFN-gamma-induced increase in electrical conductance and totally prevented the IFN-gamma-induced increase in mannitol and inulin fluxes. IL-10 did not prevent the IFN-gamma-induced abolishment of tight junctional charge selectivity but did attenuate the total increase in sodium and chloride permeability. IFN-gamma and IL-10 both separately reduced peak forskolin and carbachol-stimulated Isc. IL-10 pretreatment further enhanced the IFN-gamma-induced reduction in secretagogue-induced Isc. CONCLUSIONS In T84 epithelial monolayers, IL-10 maintains the size, but not the charge, selectivity of the epithelial tight junction in the presence of IFN-gamma. In addition, both IL-10 and IFN-gamma limit carbachol and forskolin-induced increase in Isc.
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Boggiano MM, Chandler PC, Oswald KD, Rodgers RJ, Blundell JE, Ishii Y, Beattie AH, Holch P, Allison DB, Schindler M, Arndt K, Rudolf K, Mark M, Schoelch C, Joost HG, Klaus S, Thöne-Reineke C, Benoit SC, Seeley RJ, Beck-Sickinger AG, Koglin N, Raun K, Madsen K, Wulff BS, Stidsen CE, Birringer M, Kreuzer OJ, Deng XY, Whitcomb DC, Halem H, Taylor J, Dong J, Datta R, Culler M, Ortmann S, Castañeda TR, Tschöp M. PYY3-36 as an anti-obesity drug target. Obes Rev 2005; 6:307-22. [PMID: 16246216 DOI: 10.1111/j.1467-789x.2005.00218.x] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The neuropeptide Y (NPY)/peptide YY (PYY) system has been implicated in the physiology of obesity for several decades. More recently ignited enormous interest in PYY3-36, an endogenous Y2-receptor agonist, as a promising anti-obesity compound. Despite this interest, there have been remarkably few subsequent reports reproducing or extending the initial findings, while at the same time studies finding no anti-obesity effects have surfaced. Out of 41 different rodent studies conducted (in 16 independent labs worldwide), 33 (83%) were unable to reproduce the reported effects and obtained no change or sometimes increased food intake, despite use of the same experimental conditions (i.e. adaptation protocols, routes of drug administration and doses, rodent strains, diets, drug vendors, light cycles, room temperatures). Among studies by authors in the original study, procedural caveats are reported under which positive effects may be obtained. Currently, data speak against a sustained decrease in food intake, body fat, or body weight gain following PYY3-36 administration and make the previously suggested role of the hypothalamic melanocortin system unlikely as is the existence of PYY deficiency in human obesity. We review the studies that are in the public domain which support or challenge PYY3-36 as a potential anti-obesity target.
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Research Support, N.I.H., Extramural |
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Wu X, Vallance BA, Boyer L, Bergstrom KSB, Walker J, Madsen K, O'Kusky JR, Buchan AM, Jacobson K. Saccharomyces boulardii ameliorates Citrobacter rodentium-induced colitis through actions on bacterial virulence factors. Am J Physiol Gastrointest Liver Physiol 2008; 294:G295-306. [PMID: 18032474 DOI: 10.1152/ajpgi.00173.2007] [Citation(s) in RCA: 94] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Saccharomyces boulardii has received increasing attention as a probiotic effective in the prevention and treatment of infectious and inflammatory bowel diseases. The aim of this study was to examine the ameliorating effects of S. boulardii on Citrobacter rodentium colitis in vivo and identify potential mechanisms of action. C57BL/6 mice received 2.5 x 10(8) C. rodentium by gavage on day 0, followed by S. boulardii (25 mg; 5 x 10(8) live cells) gavaged twice daily from day 2 to day 9. Animal weights were monitored until death on day 10. Colons were removed and assessed for epithelial barrier function, histology, and myeloperoxidase activity. Bacterial epithelial attachment and type III secreted proteins translocated intimin receptor Tir (the receptor for bacterial intimin) and EspB (a translocation apparatus protein) required for bacterial virulence were assayed. In infected mice, S. boulardii treatment significantly attenuated weight loss, ameliorated crypt hyperplasia (234.7 +/- 7.2 vs. 297.8 +/- 17.6 microm) and histological damage score (0.67 +/- 0.67 vs. 4.75 +/- 0.75), reduced myeloperoxidase activity (2.1 +/- 0.4 vs. 4.7 +/- 0.9 U/mg), and attenuated increased mannitol flux (17.2 +/- 5.0 vs. 31.2 +/- 8.2 nm.cm(-2).h(-1)). The ameliorating effects of S. boulardii were associated with significantly reduced numbers of mucosal adherent C. rodentium, a marked reduction in Tir protein secretion and translocation into mouse colonocytes, and a striking reduction in EspB expression and secretion. We conclude that S. boulardii maintained colonic epithelial barrier integrity and ameliorated inflammatory sequelae associated with C. rodentium infection by attenuating C. rodentium adherence to host epithelial cells through putative actions on the type III secretion system.
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Runge S, Wulff BS, Madsen K, Bräuner-Osborne H, Knudsen LB. Different domains of the glucagon and glucagon-like peptide-1 receptors provide the critical determinants of ligand selectivity. Br J Pharmacol 2003; 138:787-94. [PMID: 12642379 PMCID: PMC1573731 DOI: 10.1038/sj.bjp.0705120] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
(1) Glucagon and glucagon-like peptide-1 (GLP-1) are homologous peptide hormones with important functions in glucose metabolism. The receptors for glucagon and GLP-1 are homologous family B G-protein coupled receptors. The GLP-1 receptor amino-terminal extracellular domain is a major determinant of glucagon/GLP-1 selectivity of the GLP-1 receptor. However, the divergent residues in glucagon and GLP-1 that determine specificity for the GLP-1 receptor amino-terminal extracellular domain are not known. Less is known about how the glucagon receptor distinguishes between glucagon and GLP-1. (2) We analysed chimeric glucagon/GLP-1 peptides for their ability to bind and activate the glucagon receptor, the GLP-1 receptor and chimeric glucagon/GLP-1 receptors. The chimeric peptide GLP-1(7-20)/glucagon(15-29) was unable to bind and activate the glucagon receptor. Substituting the glucagon receptor core domain with the GLP-1 receptor core domain (chimera A) completely rescued the affinity and potency of GLP-1(7-20)/glucagon(15-29) without compromising the affinity and potency of glucagon. Substituting transmembrane segment 1 (TM1), TM6, TM7, the third extracellular loop and the intracellular carboxy-terminus of chimera A with the corresponding glucagon receptor segments re-established the ability to distinguish GLP-1(7-20)/glucagon(15-29) from glucagon. Corroborant results were obtained with the opposite chimeric peptide glucagon(1-14)/GLP-1(21-37). (3) The results suggest that the glucagon and GLP-1 receptor amino-terminal extracellular domains determine specificity for the divergent residues in the glucagon and GLP-1 carboxy-terminals respectively. The GLP-1 receptor core domain is not a critical determinant of glucagon/GLP-1 selectivity. Conversely, the glucagon receptor core domain contains two or more sub-segments which strongly determine specificity for divergent residues in the glucagon amino-terminus.
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Madsen K, Friberg U, Roos P, Edén S, Isaksson O. Growth hormone stimulates the proliferation of cultured chondrocytes from rabbit ear and rat rib growth cartilage. Nature 1983; 304:545-7. [PMID: 6877376 DOI: 10.1038/304545a0] [Citation(s) in RCA: 90] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The effect of growth hormone (GH) on various growth processes is generally considered to be indirect, mediated by GH-dependent plasma factors--somatomedins--which are produced mainly in the liver. In vitro, somatomedins stimulate a number of processes that apparently are associated with cell growth. It has been difficult, however, to induce skeletal growth by the administration of somatomedins in vivo. Daily injections of a partially purified somatomedin preparation failed to induce accumulated longitudinal bone growth using the intravital marker tetracycline or by measuring the nose-to-tail length. Administration of insulin-like growth factor I (IGF I) which is probably identical to somatomedin C, to hypophysectomized rats has been reported to increase the width of the epiphyseal plate. But although this suggests an in vivo effect of IGF I on longitudinal bone growth, such an effect has not been directly demonstrated. Recently, we reported that local administration of human GH (hGH) into the proximal cartilage growth plate of the tibia of hypophysectomized rats stimulated longitudinal bone growth on the side injected with the hormone. Furthermore, we have identified specific binding sites for hGH in cultured chondrocytes from rabbit ear and epiphyses. Here, we show that hGH, but not the structurally related polypeptides ovine prolactin or human prolactin, stimulates DNA synthesis in chondrocytes from rabbit ear and from rat rib growth plate, cultured in a chemically defined medium without the addition of serum. Our results suggest that GH directly initiates proliferation in mammalian chondrocytes.
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Jijon HB, Churchill T, Malfair D, Wessler A, Jewell LD, Parsons HG, Madsen KL. Inhibition of poly(ADP-ribose) polymerase attenuates inflammation in a model of chronic colitis. Am J Physiol Gastrointest Liver Physiol 2000; 279:G641-51. [PMID: 10960365 DOI: 10.1152/ajpgi.2000.279.3.g641] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Crohn's disease is a chronic disease characterized by oxidant-induced tissue injury and increased intestinal permeability. A consequence of oxidative damage is the accumulation of DNA strand breaks and activation of poly(ADP-ribose) polymerase (PARP), which subsequently catalyzes ADP-ribosylation of target proteins. In this study, we assessed the role of PARP in the colitis seen in interleukin (IL)-10 gene-deficient mice. IL-10 gene-deficient mice demonstrated significant alterations in colonic cellular energy status in conjunction with increased permeability, proinflammatory cytokine release, and nitrosative stress. After 14 days of treatment with the PARP inhibitor 3-aminobenzamide, IL-10 gene-deficient mice demonstrated normalized colonic permeability; reduced tumor necrosis factor-alpha and interferon-gamma secretion, inducible nitric oxide synthase expression, and nitrotyrosine levels; and significantly attenuated inflammation. Time course studies demonstrated that 3-aminobenzamide rapidly altered cellular metabolic activity and decreased cellular lactate levels. This was associated with normalization of colonic permeability and followed by a downregulation of proinflammatory cytokine release. Our data demonstrate that inhibition of PARP activity results in a marked improvement of colonic inflammatory disease and a normalization of cellular metabolic function and intestinal permeability.
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25 |
90 |
17
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Hasselbalch SG, Madsen K, Svarer C, Pinborg LH, Holm S, Paulson OB, Waldemar G, Knudsen GM. Reduced 5-HT2A receptor binding in patients with mild cognitive impairment. Neurobiol Aging 2008; 29:1830-8. [PMID: 17544547 DOI: 10.1016/j.neurobiolaging.2007.04.011] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2006] [Revised: 03/16/2007] [Accepted: 04/07/2007] [Indexed: 11/21/2022]
Abstract
Previous studies of patients with Alzheimer's disease (AD) have described reduced brain serotonin 2A (5-HT(2A)) receptor density. It is unclear whether this abnormality sets in early in the course of the disease and whether it is related to early cognitive and neuropsychiatric symptoms. We assessed cerebral 5-HT(2A) receptor binding in patients with mild cognitive impairment (MCI) and related 5-HT(2A) receptor binding to clinical symptoms. Sixteen patients with MCI of the amnestic type (mean age 73, mean MMSE 26.1) and 17 age and sex matched control subjects were studied with MRI and [(18)F]altanserin PET in a bolus-infusion approach. A significant global reduction of 20-30% in 5-HT(2A) binding (atrophy corrected) was found in most neocortical areas. Reduced 5-HT(2A) binding in the striatum correlated significantly with Neuropsychiatric Inventory depression and anxiety scores. We conclude that widespread reductions in 5-HT(2A) receptor binding were found in amnestic MCI, pointing at the presence of serotonergic dysfunction in prodromal AD. This may provide some of the pathophysiological background for the neuropsychiatric symptoms found in early AD.
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17 |
87 |
18
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Franch J, Madsen K, Djurhuus MS, Pedersen PK. Improved running economy following intensified training correlates with reduced ventilatory demands. Med Sci Sports Exerc 1998; 30:1250-6. [PMID: 9710865 DOI: 10.1097/00005768-199808000-00011] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE To compare the effects of three types of intensive run training on running economy (RE) during exhaustive running and to establish possible relationships with changes in ventilatory function and/or muscle fiber type distribution. METHODS Thirty-six male recreational runners were divided into three groups and assigned to either exhaustive distance training (DT), long-interval training (LIT), or short-interval training (SIT) three times 20-30 minxwk(-1) for 6 wk. VO(2 max) and RE were measured during treadmill running before and after training. Muscle fiber type distribution of the vastus lateralis muscle was established from biopsy material. RESULTS VO(2max) (Lxmin(-1) increased by 5.9% (P < 0.0001), 6.0% (P < 0.0001), and 3.6% (P < 0.01) in DT, LIT, and SIT, respectively, and running speed at VO(2max) by 9% (P < 0.0001), 10% (P < 0.0001), and 4% (P < 0.05), respectively. Time-to-exhaustion at 87% of pretraining VO(2max) (mean 3.83) mxs(-1) increased by 94% in DT (P < 0.0001), 67% in LIT (P < 0.0001). Running economy improved by 3.1% in DT (P < 0.05), 3.0% in LIT (P < 0.01), and 0.9% SIT (NS): pulmonary ventilation (VE) was on average 11 Lxmin(-1) lower following training (P < 0.0001). The individual decrements in VE correlated with improvements in RE (r = 0.77; P < 0.0001) and may account for 25-70% of the decrease in aerobic demand. Muscle fiber composition, and respiratory exchange ratio, stride length, and stride frequency during running were unaltered with training. CONCLUSIONS Recreational runners can improve RE and aerobic run performance by exchanging parts of their conventional aerobic distance training with intensive distance or long-interval running, whereas short-interval running is less efficient. The improvement in RE may relate to reduced ventilatory demands. Muscle fiber type distribution was unaltered with training and showed no associations with RE.
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Clinical Trial |
27 |
81 |
19
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Madsen KL. The use of probiotics in gastrointestinal disease. CANADIAN JOURNAL OF GASTROENTEROLOGY = JOURNAL CANADIEN DE GASTROENTEROLOGIE 2001; 15:817-22. [PMID: 11773948 DOI: 10.1155/2001/690741] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Probiotics are living microorganisms that can affect the host in a beneficial manner. Prebiotics are nondigestible food ingredients that stimulate the growth and activity of probiotic bacteria already established in the colon. Efficacy of probiotic compounds has been shown in a wide range of gastrointestinal diseases. Lactobacillus GG alone, or the combination of Bifidobacterium bifidum and Streptococcus thermophilus, is effective in the treatment of Clostridium difficile, as well as in preventing the frequency and severity of infectious acute diarrhea in children. Prevention of antibiotic-induced diarrhea with the concomitant administration of either Lactobacillus GG or Saccharomyces boulardii has been demonstrated. The most successful studies involve the use of Lactobacillus GG at a dose of 1 x 1010 viable organisms per day and the yeast boulardii at a dose of 1 g/day. A probiotic preparation (VSL#3 - 6 g/day) that uses a combination of three species of Bifidobacterium, four strains of Lactobacillus and one strain of Streptocccus has shown promise in maintaining remission in ulcerative colitis and pouchitis, as well as in preventing the postoperative recurrence of Crohn's disease. The mechanism of action of probiotics may include receptor competition, effects on mucin secretion or probiotic immunomodulation of gut-associated lymphoid tissue. Oral administration of probiotic compounds has been demonstrated to be well tolerated and safe. However, while probiotics have the potential to improve human health and to prevent and treat some diseases, major improvements are needed in labelling and quality assurance procedures for probiotic compounds. In addition, well planned and controlled clinical studies are necessary to delineate fully the potential for probiotic compounds.
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Review |
24 |
80 |
20
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Madsen KL, Bhatia VK, Gether U, Stamou D. BAR domains, amphipathic helices and membrane-anchored proteins use the same mechanism to sense membrane curvature. FEBS Lett 2010; 584:1848-55. [PMID: 20122931 DOI: 10.1016/j.febslet.2010.01.053] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2010] [Accepted: 01/26/2010] [Indexed: 12/24/2022]
Abstract
The internal membranes of eukaryotic cells are all twists and bends characterized by high curvature. During recent years it has become clear that specific proteins sustain these curvatures while others simply recognize membrane shape and use it as "molecular information" to organize cellular processes in space and time. Here we discuss this new important recognition process termed membrane curvature sensing (MCS). First, we review a new fluorescence-based experimental method that allows characterization of MCS using measurements on single vesicles and compare it to sensing assays that use bulk/ensemble liposome samples of different mean diameter. Next, we describe two different MCS protein motifs (amphipathic helices and BAR domains) and suggest that in both cases curvature sensitive membrane binding results from asymmetric insertion of hydrophobic amino acids in the lipid membrane. This mechanism can be extended to include the insertion of alkyl chain in the lipid membrane and consequently palmitoylated and myristoylated proteins are predicted to display similar curvature sensitive binding. Surprisingly, in all the aforementioned cases, MCS is predominantly mediated by a higher density of binding sites on curved membranes instead of higher affinity as assumed so far. Finally, we integrate these new insights into the debate about which motifs are involved in sensing versus induction of membrane curvature and what role MCS proteins may play in biology.
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Review |
15 |
77 |
21
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Lohmander S, Moskalewski S, Madsen K, Thyberg J, Friberg U. Influence of colchicine on the synthesis and secretion of proteoglycans and collagen by fetal guinea pig chondrocytes. Exp Cell Res 1976; 99:333-45. [PMID: 131691 DOI: 10.1016/0014-4827(76)90591-7] [Citation(s) in RCA: 76] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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49 |
76 |
22
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Schlesser JE, Gerdes R, Ravishankar S, Madsen K, Mowbray J, Teo AYL. Survival of a five-strain cocktail of Escherichia coli O157:H7 during the 60-day aging period of cheddar cheese made from unpasteurized milk. J Food Prot 2006; 69:990-8. [PMID: 16715794 DOI: 10.4315/0362-028x-69.5.990] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The U.S. Food and Drug Administration Standard of Identity for Cheddar cheeses requires pasteurization of the milk, or as an alternative treatment, a minimum 60-day aging at > or =2 degrees C for cheeses made from unpasteurized milk, to reduce the number of viable pathogens that may be present to an acceptable risk. The objective of this study was to investigate the adequacy of the 60-day minimum aging to reduce the numbers of viable pathogens and evaluate milk subpasteurization heat treatment as a process to improve the safety of Cheddar cheeses made from unpasteurized milk. Cheddar cheese was made from unpasteurized milk inoculated with 10(1) to 10(5) CFU/ml of a five-strain cocktail of acid-tolerant Escherichia coli O157:H7. Samples were collected during the cheese manufacturing process. After pressing, the cheese blocks were packaged into plastic bags, vacuum sealed, and aged at 7 degrees C. After 1 week, the cheese blocks were cut into smaller-size uniform pieces and then vacuum sealed in clear plastic pouches. Samples were plated and enumerated for E. coli O157:H7. Populations of E. coli O157:H7 increased during the cheese-making operations. Population of E. coli O157:H7 in cheese aged for 60 and 120 days at 7 degrees C decreased less than 1 and 2 log, respectively. These studies confirm previous reports that show 60-day aging is inadequate to eliminate E. coli O157:H7 during cheese ripening. Subpasteurization heat-treatment runs were conducted at 148 degrees F (64.4 degrees C) for 17.5 s on milk inoculated with E. coli O157:H7 at 10(5) CFU/ml. These heat-treatment runs resulted in a 5-log E. coli O157: H7 reduction.
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70 |
23
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Madsen KL, Yanchar NL, Sigalet DL, Reigel T, Fedorak RN. FK506 increases permeability in rat intestine by inhibiting mitochondrial function. Gastroenterology 1995; 109:107-14. [PMID: 7540994 DOI: 10.1016/0016-5085(95)90274-0] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
BACKGROUND & AIMS Under normal physiological conditions, the intestine presents an adenosine triphosphate (ATP)-dependent barrier to luminal contents. Disruption of this barrier function can occur when cellular metabolism is compromised. This study examined the effects of FK506 on intestinal permeability and enterocyte metabolic function in Lewis rats. METHODS Rats were administered FK506 at a dose of 0.1, 0.5, or 2 mg/kg on alternate days for 6 weeks. Intestinal permeability was assessed by measuring urinary recovery of 99mTc-diethylenetriamine pentacetate, and electrophysiological conductance measurements were performed in Ussing chambers. Metabolic function was assessed in isolated enterocytes by measuring total ATP and CO2 release from [14C]pyruvate and [14C]glucose. RESULTS Rats treated with FK506 showed a dose-dependent reduction in weight gain as well as increased in vivo and in vitro intestinal permeability. There was no difference in plasma creatinine or urinary output. Changes in permeability correlated with reduced ATP levels and CO2 release because of diminished mitochondrial function. Lactate production, as a measure of glycolytic activity, was not altered by FK506. CONCLUSIONS In a dose-dependent manner, FK506 treatment in rats reduces weight gain, increases intestinal permeability, and decreases the ability of the small intestine to use glucose as an energy source.
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30 |
67 |
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Madsen K, MacLean DA, Kiens B, Christensen D. Effects of glucose, glucose plus branched-chain amino acids, or placebo on bike performance over 100 km. J Appl Physiol (1985) 1996; 81:2644-50. [PMID: 9018517 DOI: 10.1152/jappl.1996.81.6.2644] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
This study was undertaken to determine the effects of ingesting either glucose (trial G) or glucose plus branched-chain amino acids (BCAA: trial B), compared with placebo (trial P), during prolonged exercise. Nine well-trained cyclists with a maximal oxygen uptake of 63.1 +/- 1.5 ml O2. min-1.kg-1 performed three laboratory trials consisting of 100 km of cycling separated by 7 days between each trial. During these trials, the subjects were encouraged to complete the 100 km as fast as possible on their own bicycles connected to a magnetic brake. No differences in performance times were observed between the three trials (160.1 +/- 4.1, 157.2 +/- 4.5, and 159.8 +/- 3.7 min, respectively). In trial B, plasma BCAA levels increased from 339 +/- 28 microM at rest to 1,026 +/- 62 microM after exercise (P < 0.01). Plasma ammonia concentrations increased during the entire exercise period for all three trials and were significantly higher in trial B compared with trials G and P (P < 0.05). The respiratory exchange ratio was similar in the three trials during the first 90 min of exercise; thereafter, it tended to drop more in trial P than in trials G and B. These data suggest that neither glucose nor glucose plus BCAA ingestion during 100 km of cycling enhance performance in well-trained cyclists.
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Clinical Trial |
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25
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Kasliwal MM, Nakar E, Singer LP, Kaplan DL, Cook DO, Van Sistine A, Lau RM, Fremling C, Gottlieb O, Jencson JE, Adams SM, Feindt U, Hotokezaka K, Ghosh S, Perley DA, Yu PC, Piran T, Allison JR, Anupama GC, Balasubramanian A, Bannister KW, Bally J, Barnes J, Barway S, Bellm E, Bhalerao V, Bhattacharya D, Blagorodnova N, Bloom JS, Brady PR, Cannella C, Chatterjee D, Cenko SB, Cobb BE, Copperwheat C, Corsi A, De K, Dobie D, Emery SWK, Evans PA, Fox OD, Frail DA, Frohmaier C, Goobar A, Hallinan G, Harrison F, Helou G, Hinderer T, Ho AYQ, Horesh A, Ip WH, Itoh R, Kasen D, Kim H, Kuin NPM, Kupfer T, Lynch C, Madsen K, Mazzali PA, Miller AA, Mooley K, Murphy T, Ngeow CC, Nichols D, Nissanke S, Nugent P, Ofek EO, Qi H, Quimby RM, Rosswog S, Rusu F, Sadler EM, Schmidt P, Sollerman J, Steele I, Williamson AR, Xu Y, Yan L, Yatsu Y, Zhang C, Zhao W. Illuminating gravitational waves: A concordant picture of photons from a neutron star merger. Science 2017; 358:1559-1565. [PMID: 29038373 DOI: 10.1126/science.aap9455] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Accepted: 10/05/2017] [Indexed: 11/02/2022]
Abstract
Merging neutron stars offer an excellent laboratory for simultaneously studying strong-field gravity and matter in extreme environments. We establish the physical association of an electromagnetic counterpart (EM170817) with gravitational waves (GW170817) detected from merging neutron stars. By synthesizing a panchromatic data set, we demonstrate that merging neutron stars are a long-sought production site forging heavy elements by r-process nucleosynthesis. The weak gamma rays seen in EM170817 are dissimilar to classical short gamma-ray bursts with ultrarelativistic jets. Instead, we suggest that breakout of a wide-angle, mildly relativistic cocoon engulfing the jet explains the low-luminosity gamma rays, the high-luminosity ultraviolet-optical-infrared, and the delayed radio and x-ray emission. We posit that all neutron star mergers may lead to a wide-angle cocoon breakout, sometimes accompanied by a successful jet and sometimes by a choked jet.
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Research Support, Non-U.S. Gov't |
8 |
61 |