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Jensen VF, Jensen NK, Schefe LH, Sigh J, Akintomide A, Kaaber K, Moesgaard SG, Pedersen MH. The Non-Human Primate in Safety Assessment of a Bifunctional Long-Acting Insulin Analogue. Int J Toxicol 2023; 42:254-268. [PMID: 36799227 DOI: 10.1177/10915818231156898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Species selection plays a pivotal part during non-clinical safety assessment in drug development. If possible, use of non-human primates (NHPs) should be avoided due to ethical considerations. However, limiting factors as lack of pharmacologic activity in other species could necessitate use of NHPs. LAI-PCSK9i is a bi-functional molecule combining a long-acting insulin analogue with a PCSK9 inhibitor peptide aiming to provide glycaemic control and to reduce plasma LDL concentrations. The NHP was chosen for the safety assessment of LAI-PCSK9i being the most relevant species with basal levels and plasma lipid composition closest to humans, while the dog and initially also the minipig were deemed irrelevant due to lack of pharmacologic activity on LDL-lowering and biological differences in lipid profiles. An in vivo tolerability and toxicokinetic study of LAI-PCSK9i in NHPs showed recurrent and severe hypoglycaemia at very low doses. Therefore, the minipig was re-evaluated and a follow-up study thoroughly assessing blood glucose and cholesterol levels and clinical signs illustrated that minipigs dosed with LAI-PCSK9i, tolerated the compound and LAI-PCSK9i decreased glucose and LDL over time. This work underlines that careful consideration is required when selecting species during safety assessment in drug development. The tolerability issue in NHPs led to the subsequent selection of the minipig for safety evaluation of LAI-PCSK9i although as a suboptimal alternative, which unexpectedly had a measurable pharmacologic response on LDL lowering. In conclusion, the NHPs may be unsuitable as test species for safety assessment of long-acting insulin analogues due to high sensitivity to recurring hypoglycaemic episodes.
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Affiliation(s)
- Vivi Fh Jensen
- Global Drug Discovery and Development Sciences, 1450Novo Nordisk A/S, Maaloev, Denmark
| | - Nikolai K Jensen
- Global Drug Discovery and Development Sciences, 1450Novo Nordisk A/S, Maaloev, Denmark
| | - Line H Schefe
- Global Drug Discovery and Development Sciences, 1450Novo Nordisk A/S, Maaloev, Denmark
| | - Jens Sigh
- Global Drug Discovery and Development Sciences, 1450Novo Nordisk A/S, Maaloev, Denmark
| | | | | | | | - Mona H Pedersen
- Global Drug Discovery and Development Sciences, 1450Novo Nordisk A/S, Maaloev, Denmark
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Cremer SE, Zois NE, Moesgaard SG, Ravn N, Cirera S, Honge JL, Smerup MH, Hasenkam JM, Sloth E, Leifsson PS, Falk T, Oyama MA, Orton C, Martinussen T, Olsen LH. Serotonin markers show altered transcription levels in an experimental pig model of mitral regurgitation. Vet J 2014; 203:192-8. [PMID: 25599900 DOI: 10.1016/j.tvjl.2014.12.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2014] [Revised: 12/01/2014] [Accepted: 12/16/2014] [Indexed: 12/18/2022]
Abstract
Serotonin (5-hydroxytryptamine, 5-HT) signalling is implicated in the pathogenesis of myxomatous mitral valve disease (MMVD) through 5-HT1B receptor (R), 5-HT2AR and 5-HT2BR-induced myxomatous pathology. Based on increased tryptophan hydroxylase-1 (TPH-1) and decreased serotonin re-uptake transporter (SERT) in MMVD-affected valves, increased valvular 5-HT synthesis and decreased clearance have been suggested. It remains unknown how haemodynamic changes associated with mitral regurgitation (MR) affect 5-HT markers in the mitral valve, myocardium and circulation. Twenty-eight pigs underwent surgically induced MR or sham-operation, resulting in three MR groups: control (CON, n = 12), mild MR (mMR, n = 10) and severe MR (sMR, n = 6). The gene expression levels of 5-HT1BR, 5-HT2AR, 5-HT2BR, SERT and TPH-1 were analysed using quantitative PCR (qPCR) in the mitral valve (MV), anterior papillary muscle (AP) and left ventricle (LV). MV 5-HT2BR was also analysed with immunohistochemistry (IHC) in relation to histological lesions and valvular myofibroblasts. All 5-HTR mRNAs were up-regulated in MV compared to AP and LV (P <0.01). In contrast, SERT and TPH-1 were up-regulated in AP and LV compared to MV (P <0.05). In MV, mRNA levels were increased for 5-HT2BR (P = 0.02) and decreased for SERT (P = 0.03) in sMR vs. CON. There were no group differences in 5-HT2BR staining (IHC) but co-localisation was found with α-SMA-positive cells in 91% of all valves and with 33% of histological lesions. In LV, 5-HT1BR mRNA levels were increased in sMR vs. CON (P = 0.01). In conclusion, these data suggest that MR may affect mRNA expression of valvular 5-HT2BR and SERT, and left ventricular 5-HT1BR in some pigs.
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Affiliation(s)
- S E Cremer
- Department of Veterinary Disease Biology, University of Copenhagen, Frederiksberg, Denmark
| | - N E Zois
- Department of Clinical Biochemistry, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | | | - N Ravn
- Department of Cardiothoracic and Vascular Surgery, Aarhus University Hospital, Aarhus, Denmark
| | - S Cirera
- Department of Veterinary Clinical and Animal Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - J L Honge
- Department of Cardiothoracic and Vascular Surgery, Aarhus University Hospital, Aarhus, Denmark
| | - M H Smerup
- Department of Cardiothoracic and Vascular Surgery, Aarhus University Hospital, Aarhus, Denmark
| | - J M Hasenkam
- Department of Cardiothoracic and Vascular Surgery, Aarhus University Hospital, Aarhus, Denmark
| | - E Sloth
- Department of Anaesthesiology and Intensive Care Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - P S Leifsson
- Department of Veterinary Disease Biology, University of Copenhagen, Frederiksberg, Denmark
| | - T Falk
- Department of Veterinary Disease Biology, University of Copenhagen, Frederiksberg, Denmark
| | - M A Oyama
- Department of Clinical Studies, University of Pennsylvania, Philadelphia, PA, USA
| | - C Orton
- Department of Clinical Sciences, Colorado State University, Fort Collins, CO, USA
| | - T Martinussen
- Department of Biostatistics, University of Copenhagen, Copenhagen, Denmark
| | - L H Olsen
- Department of Veterinary Disease Biology, University of Copenhagen, Frederiksberg, Denmark.
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Abstract
Oral dosing by gavage is often used to test compounds in minipigs. This method is also used for certain nutritional studies that require exact dosing. This procedure may be stressful for the animal and requires the assistance of more than one technician. We investigated whether a gastrostomy tube could be placed and maintained in Göttingen minipigs using a single port laparoscopic technique. As part of another study, laparoscopic gastrostomy tube placement was performed in 12 Göttingen minipigs (32 ± 2 kg) under general anesthesia. The procedure involved single port laparoscopic visualization of the stomach and placement of a locking pigtail catheter into the fundus region of the stomach. The minipigs were followed for three weeks after surgery and macroscopic and microscopic tissue reactions were evaluated at necropsy. All catheters were successfully placed and were easy to use. At necropsy it was evident that the catheter had entered the stomach in the fundus region in 11/12 of the animals. In one animal the catheter had entered the antrum region. None of the animals developed leakage or clinically detectable reactions to the gastrostomy tube. Histopathologically, only discrete changes were observed. Single port laparoscopic tube gastrostomy with a locking pigtail catheter is safe, simple and reliable and is an appropriate alternative to, for example, percutaneous endoscopic gastrostomy, when long-term enteral delivery of pharmacological or nutritional compounds is needed. The use of the gastrostomy tube was easy and, based on subjective assessment, feeding was minimally stressful to the animals.
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Affiliation(s)
- MM Birck
- Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - A Vegge
- Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
- Diabetes Pharmacology, Novo Nordisk A/S, Måløv, Denmark
| | - SG Moesgaard
- Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
- Biopharm Toxicology and Safety Pharmacology, Novo Nordisk A/S, Måløv, Denmark
| | - T Eriksen
- Department of Veterinary Clinical and Animal Science, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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Ludvigsen TP, Wiinberg N, Jensen CJ, Callesen AT, Andersen RW, Jørgensen ASH, Christoffersen BØ, Pedersen HD, Moesgaard SG, Olsen LH. Noninvasive assessment of pulse-wave velocity and flow-mediated vasodilation in anesthetized Göttingen minipigs. Comp Med 2014; 64:471-477. [PMID: 25527028 PMCID: PMC4275083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Revised: 04/02/2014] [Accepted: 05/08/2014] [Indexed: 06/04/2023]
Abstract
Few methods for noninvasive assessment of arterial stiffness and endothelial dysfunction in porcine models are available. The aim of this study was to evaluate methods for assessment of arterial stiffness and endothelial dysfunction in anesthetized Göttingen minipigs. Pulse-wave velocity (PWV) was assessed in male Göttingen minipigs (n = 8; age approximately 60 wk) by using applanation tonometry of the carotid and femoral arteries. In addition, flow-mediated vasodilation (FMD) was assessed by using vascular ultrasonography of the brachial artery to evaluate endothelial dysfunction. To evaluate the reproducibility of the methods, minipigs were anesthetized by intravenous infusion of ketamine and midazolam and examined every other day for a total of 3 trials. Neither examination day nor systolic, diastolic, or mean arterial blood pressure statistically influenced PWV or FMD. The median interexamination coefficient of variation was 17% for PWV and 59% for FMD. Measured values of PWV corresponded largely to those in clinically healthy humans, but FMD values were lower than expected for lean, young animals. Although the ketamine-midazolam anesthesia we used has been associated with minor hemodynamic effects in vivo, in vitro studies suggest that both drugs are vasodilatory. Therefore anesthesia might have influenced the endothelial response, contributing to the modest FMD response and the concurrent high coefficients of variation that we noted. We conclude that PWV—but not FMD—showed acceptable interexamination variation for its potential application in porcine models.
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Affiliation(s)
- Trine P Ludvigsen
- Department of Veterinary Disease Biology, University of Copenhagen, Frederiksberg, Denmark; Novo Nordisk A/S, Måløv, Denmark
| | - Niels Wiinberg
- Department of Clinical Physiology and Nuclear Medicine, Frederiksberg Hospital, Frederiksberg, Denmark
| | - Christina J Jensen
- Department of Veterinary Disease Biology, University of Copenhagen, Frederiksberg, Denmark
| | - Annemette T Callesen
- Department of Veterinary Disease Biology, University of Copenhagen, Frederiksberg, Denmark
| | - Regitze W Andersen
- Department of Veterinary Disease Biology, University of Copenhagen, Frederiksberg, Denmark
| | - Anne Sofie H Jørgensen
- Department of Veterinary Disease Biology, University of Copenhagen, Frederiksberg, Denmark
| | | | | | | | - Lisbeth H Olsen
- Department of Veterinary Disease Biology, University of Copenhagen, Frederiksberg, Denmark.
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Moesgaard SG, Aupperle H, Rajamäki MM, Falk T, Rasmussen CE, Zois NE, Olsen LH. Matrix metalloproteinases (MMPs), tissue inhibitors of metalloproteinases (TIMPs) and transforming growth factor-β (TGF-β) in advanced canine myxomatous mitral valve disease. Res Vet Sci 2014; 97:560-7. [PMID: 25458505 DOI: 10.1016/j.rvsc.2014.10.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Revised: 09/28/2014] [Accepted: 10/05/2014] [Indexed: 11/16/2022]
Abstract
This study investigated mitral valve and myocardial protein and gene expression of matrix metalloproteinases (MMPs), their tissue inhibitors (TIMPs) and transforming growth factor-β (TGF-β) and plasma MMP and TGF-β concentrations in age-matched dog groups euthanized due to either advanced myxomatous mitral valve disease (MMVD) or other reasons. Furthermore, echocardiographic data and lumen/area ratio were correlated with tissue and plasma levels of MMPs, TIMPs and TGF-βs. Mitral valve and myocardial gene expression of MMP2, MMP14, TGF-β1 and TGF-β2 were increased and plasma MMP9 was decreased in advanced MMVD dogs. Myocardial gene expression of TIMP2 and TIMP3 were increased in advanced MMVD. All affected markers correlated to echocardiographic parameters. Significantly narrowed lumen/area ratio was associated with increased myocardial expression of MMP2, MMP14, TIMP2 and TIMP3. No differences in tissue protein expression were recorded. MMP2, MMP14, TIMP2, TIMP3, TGF-β1 and TGF-β2 appear to play a local role in the development of advanced MMVD.
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Affiliation(s)
| | | | - M M Rajamäki
- Department of Equine and Small Animal Medicine, Faculty of Veterinary Medicine, University of Helsinki, Finland
| | - T Falk
- Din Veterinaer, Helsingborg, Sweden
| | | | - N E Zois
- Department of Clinical Biochemistry, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - L H Olsen
- Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark.
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Ravn N, Zois NE, Moesgaard SG, Honge JL, Smerup MH, Hasenkam JM, Sloth E, Cremer SE, Olsen LH. Development of left ventricular hypertrophy in a novel porcine model of mitral regurgitation. SCAND CARDIOVASC J 2014; 48:189-95. [DOI: 10.3109/14017431.2014.895850] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Boonen HCM, Moesgaard SG, Birck MM, Christoffersen BØ, Cirera S, Heegaard PMH, Højbøge TR, Jensen LJ, Mortensen A, Olsen LH, Sheykhzade M, Tang J, Lykkesfeldt J. Functional network analysis of obese and lean Göttingen minipigs elucidates changes in oxidative and inflammatory networks in obese pigs. Pflugers Arch 2014; 466:2167-76. [DOI: 10.1007/s00424-014-1486-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Revised: 02/03/2014] [Accepted: 02/14/2014] [Indexed: 11/24/2022]
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Rasmussen CE, Falk T, Domanjko Petrič A, Schaldemose M, Zois NE, Moesgaard SG, Ablad B, Nilsen HY, Ljungvall I, Höglund K, Häggström J, Pedersen HD, Bland JM, Olsen LH. Holter monitoring of small breed dogs with advanced myxomatous mitral valve disease with and without a history of syncope. J Vet Intern Med 2014; 28:363-70. [PMID: 24417236 PMCID: PMC4857997 DOI: 10.1111/jvim.12290] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2012] [Revised: 10/08/2013] [Accepted: 11/26/2013] [Indexed: 11/30/2022] Open
Abstract
Background Syncope is a transient loss of consciousness occasionally occurring in dogs with advanced myxomatous mitral valve disease (MMVD). Objective (1) To study ECG changes during syncopal episodes in dogs with advanced MMVD and (2) to compare the occurrence of arrhythmias and changes in heart rate variability (HRV) between dogs with advanced MMVD with and without a history of syncope. Animals Forty‐three privately owned dogs (<15 kg) with advanced MMVD: 21 with and 22 without a history of syncope. Methods Prospective study with dogs recruited for an evaluation including history, physical examination, echocardiography, and arrhythmia and HRV analysis performed on 24‐hour Holter recordings. Results A syncopal episode was observed during Holter monitoring in 4 dogs: 3 dogs had sinus rhythm and 1 dog had sinus arrest followed by escape rhythm. An arrhythmia variable representing sinus arrhythmia was significantly lower in dogs with a history of syncope than in those without (P = .008). Eight of 26 HRV variables were significantly different between dogs with and without a history of syncope. Conclusions and Clinical Importance Compared with dogs without a history of syncope, dogs with advanced MMVD and a history of syncope did not have a higher occurrence of arrhythmias, but had less sinus arrhythmia, and had changes in HRV variables representing decreased overall HRV, decreased parasympathetic, and increased sympathetic modulation of heart rate.
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Affiliation(s)
- C E Rasmussen
- Department of Veterinary Clinical and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark
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Rødgaard T, Skovgaard K, Moesgaard SG, Cirera S, Christoffersen BØ, Heegaard PMH. Extensive changes in innate immune gene expression in obese Göttingen minipigs do not lead to changes in concentrations of circulating cytokines and acute phase proteins. Anim Genet 2013; 45:67-73. [PMID: 24106888 DOI: 10.1111/age.12090] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/19/2013] [Indexed: 12/22/2022]
Abstract
The usefulness of Göttingen minipigs as models for obesity and obesity-related pathologies is well established. The low-grade inflammation associated with obesity involves a range of innate immune factors; however, to our knowledge, the impact of obesity on innate immune factor expression has not been studied in Göttingen minipigs. Therefore, we studied the expression of innate immune genes in liver and adipose tissues as well as serum concentrations of cytokines and acute phase proteins in obese vs. lean Göttingen minipigs. In the liver, of 35 investigated genes, the expression of nine was significantly different in obese pigs (three up-regulated, six down-regulated). Of 33 genes in adipose tissues, obesity was associated with changed expression of 12 genes in the visceral adipose tissue (VAT) (three up-regulated), 11 in the abdominal retroperitoneal adipose tissue (RPAT) (seven of these up-regulated) and eight in the subcutaneous adipose tissue (SAT) from the neck (five of which were up-regulated). Obesity-associated expression changes were observed for three genes in all adipose tissues, namely chemokine (C-C motif) ligand 3-like 1 (up-regulated), CD200 molecule (down-regulated) and interleukin 1 receptor antagonist (up-regulated) with interleukin 1 receptor antagonist being the most highly regulated gene in both VAT and RPAT. Looking at patterns of expression across the three types of adipose tissues, obesity was associated with an increased number of acute phase proteins differentially expressed between adipose tissues and a decreased tissue-specific expression of cytokines and chemokines. In contrast to obese humans, no changes in serum concentrations of haptoglobin, C-reactive protein, serum amyloid A, tumor necrosis factor-α and interleukin 6 were found in obese Göttingen minipigs.
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Affiliation(s)
- T Rødgaard
- National Veterinary Institute, Technical University of Denmark, Frederiksberg C, 1870, Denmark
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Cirera S, Jensen MS, Elbrønd VS, Moesgaard SG, Christoffersen BØ, Kadarmideen HN, Skovgaard K, Bruun CV, Karlskov-Mortensen P, Jørgensen CB, Fredholm M. Expression studies of six human obesity-related genes in seven tissues from divergent pig breeds. Anim Genet 2013; 45:59-66. [PMID: 24033492 DOI: 10.1111/age.12082] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/19/2013] [Indexed: 02/03/2023]
Abstract
Obesity has reached epidemic proportions globally and has become the cause of several major health risks worldwide. Presently, more than 100 loci have been related to obesity and metabolic traits in humans by genome-wide association studies. The complex genetic architecture behind obesity has triggered a need for the development of better animal models than rodents. The pig has emerged as a very promising biomedical model to study human obesity traits. In this study, we have characterized the expression patterns of six obesity-related genes, leptin (LEP), leptin receptor (LEPR), melanocortin 4 receptor (MC4R), fat mass and obesity associated (FTO), neuronal growth regulator 1 (NEGR)1 and adiponectin (ADIPOQ), in seven obesity-relevant tissues (liver; muscle; pancreas; hypothalamus; and retroperitoneal, subcutaneous and mesenteric adipose tissues) in two pig breeds (production pigs and Göttingen minipigs) that deviate phenotypically and genetically from each other with respect to obesity traits. We observe significant differential expression for LEP, LEPR and ADIPOQ in muscle and in all three adipose tissues. Interestingly, in pancreas, LEP expression is only detected in the fat minipigs. FTO shows significant differential expression in all tissues analyzed, and NEGR1 shows significant differential expression in muscle, pancreas, hypothalamus and subcutaneous adipose tissue. The MC4R transcript can be detected only in hypothalamus. In general, the expression profiles of the investigated genes are in accordance with those observed in human studies. Our study shows that both the differences between the investigated breeds and the phenotypic state with respect to obesity/leanness play a large role for differential expression of the obesity-related genes.
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Affiliation(s)
- S Cirera
- Department of Veterinary Clinical and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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Zois NE, Olsen NT, Moesgaard SG, Rasmussen CE, Falk T, Häggström J, Pedersen HD, Møller JE, Olsen LH. Left ventricular twist and circumferential strain in dogs with myxomatous mitral valve disease. J Vet Intern Med 2013; 27:875-83. [PMID: 23731222 DOI: 10.1111/jvim.12114] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Revised: 02/24/2013] [Accepted: 04/17/2013] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND During the cardiac cycle, the ventricle undergoes a twisting motion because of the oblique orientation of the left ventricular (LV) myofibers. This can be quantified by speckle-tracking echocardiography (STE). In mitral regurgitation (MR) in humans, the short axis deformation has been suggested as being pivotal to LV function. Decreased and delayed LV twist has been described in experimental MR, but has not been studied in myxomatous mitral valve disease (MMVD). HYPOTHESES (1) Magnitude (CSt) and rate (CSRs) of systolic circumferential deformation decrease before the onset of congestive heart failure (CHF); (2) magnitude and rate of LV twist decrease, and onset of untwist is delayed, with increasing MMVD severity. ANIMALS A total of 97 privately owned small- to medium-sized dogs. METHODS Severity of MMVD was assessed by echocardiography and presence of clinical signs of CHF. Magnitude and rate of LV twist and circumferential deformation were evaluated by STE. RESULTS Dogs with CHF receiving treatment had increased CSt, CSRs, early diastolic untwisting rate, and delayed onset of untwist compared to dogs with minimal MMVD and increased systolic twist compared to dogs with mild MMVD (all P < .01). CSt and time to onset of untwist increased with echocardiographic variables of MR severity (all P < .002). CSRs and several LV twist variables decreased with increasing systolic LV internal diameter (all P < .01). CONCLUSIONS AND CLINICAL IMPORTANCE No STE-derived variable was decreased before onset of CHF. In dogs with CHF receiving treatment, the delayed onset of relaxation might indicate LV dysfunction and the hyperdynamic CSt and LV twist reflect compensatory mechanisms.
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Affiliation(s)
- N E Zois
- Department of Veterinary Clinical and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark.
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Pedersen R, Ingerslev HC, Sturek M, Alloosh M, Cirera S, Christoffersen BØ, Moesgaard SG, Larsen N, Boye M. Characterisation of gut microbiota in Ossabaw and Göttingen minipigs as models of obesity and metabolic syndrome. PLoS One 2013; 8:e56612. [PMID: 23437186 PMCID: PMC3577853 DOI: 10.1371/journal.pone.0056612] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2012] [Accepted: 01/11/2013] [Indexed: 01/10/2023] Open
Abstract
Background Recent evidence suggests that the gut microbiota is an important contributing factor to obesity and obesity related metabolic disorders, known as the metabolic syndrome. The aim of this study was to characterise the intestinal microbiota in two pig models of obesity namely Göttingen minipigs and the Ossabaw minipigs. Methods and Findings The cecal, ileal and colonic microbiota from lean and obese Osabaw and Göttingen minipigs were investigated by Illumina-based sequencing and by high throughput qPCR, targeting the 16S rRNA gene in different phylogenetic groups of bacteria. The weight gain through the study was significant in obese Göttingen and Ossabaw minipigs. The lean Göttingen minipigs’ cecal microbiota contained significantly higher abundance of Firmicutes (P<0.006), Akkermensia (P<0.01) and Methanovibribacter (P<0.01) than obese Göttingen minipigs. The obese Göttingen cecum had higher abundances of the phyla Spirochaetes (P<0.03), Tenericutes (P<0.004), Verrucomicrobia (P<0.005) and the genus Bacteroides (P<0.001) compared to lean minipigs. The relative proportion of Clostridium cluster XIV was 7.6-fold higher in cecal microbiota of obese Göttingen minipigs as compared to lean. Obese Ossabaw minipigs had a higher abundance of Firmicutes in terminal ileum and lower abundance of Bacteroidetes in colon than lean Ossabaw minipigs (P<0.01). Obese Ossabaws had significantly lower abundances of the genera Prevotella and Lactobacillus and higher abundance of Clostridium in their colon than the lean Ossabaws. Overall, the Göttingen and Ossabaw minipigs displayed different microbial communities in response to diet-induced obesity in the different sections of their intestine. Conclusion Obesity-related changes in the composition of the gut microbiota were found in lean versus obese Göttingen and Ossabaw minipigs. In both pig models diet seems to be the defining factor that shapes the gut microbiota as observed by changes in different bacteria divisions between lean and obese minipigs.
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Affiliation(s)
- Rebecca Pedersen
- Department of Bacteriology Pathology and Parasitology, National Veterinary Institute, Technical University of Denmark, Frederiksberg C, Denmark
| | - Hans-Christian Ingerslev
- Department of Bacteriology Pathology and Parasitology, National Veterinary Institute, Technical University of Denmark, Frederiksberg C, Denmark
| | - Michael Sturek
- Department of Cellular & Integrative Physiology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Mouhamad Alloosh
- Department of Cellular & Integrative Physiology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Susanna Cirera
- Department of Veterinary Clinical and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg C, Denmark
| | | | | | | | - Mette Boye
- Department of Bacteriology Pathology and Parasitology, National Veterinary Institute, Technical University of Denmark, Frederiksberg C, Denmark
- * E-mail:
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Cirera S, Moesgaard SG, Zois NE, Ravn N, Goetze JP, Cremer SE, Teerlink T, Leifsson PS, Honge JL, Hasenkam JM, Olsen LH. Plasma proANP and SDMA and microRNAs are associated with chronic mitral regurgitation in a pig model. Endocr Connect 2013; 2:161-71. [PMID: 24029364 PMCID: PMC3845709 DOI: 10.1530/ec-13-0051] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVE NON-ISCHEMIC MITRAL REGURGITATION (MR) IS PRIMARILY CAUSED BY MYXOMATOUS MITRAL VALVE (MV) DISEASE LEADING TO ADAPTIVE REMODELING, ENLARGEMENT, AND DYSFUNCTION OF THE LEFT VENTRICLE. THE AIM OF THIS STUDY WAS TO EXAMINE THE REGULATION OF PLASMA MARKERS AND SEVERAL CARDIAC KEY GENES IN A NOVEL PORCINE MODEL OF NON-ISCHEMIC MR. METHODS AND RESULTS Twenty-eight production pigs (Sus scrofa) were randomized to experimental MR or sham surgery controls. MR was induced by external suture(s) through the posterior MV leaflet and quantified using echocardiography. The experimental group was subdivided into mild MR (mMR, MR=20-50%, n=10) and moderate/severe MR (sMR, MR >50%, n=6) and compared with controls (CON, MR ≤10%, n=12). Eight weeks postoperatively, follow-up examinations were performed followed by killing. Circulating concentrations of pro-atrial natriuretic peptide (proANP), l-arginine, asymmetric dimethylarginine, and symmetric dimethylarginine (SDMA) were measured. MV, anterior papillary muscle, and left ventricular free wall tissues were collected to quantify mRNA expression of eNOS (NOS3), iNOS (NOS2), MMP9, MMP14, ANP (NPPA), BNP (NPPB), and TGFB1, 2, and 3 and five microRNAs by quantitative real-time PCR. Pigs with sMR displayed markedly increased plasma proANP and SDMA concentrations compared with both controls and mMR (P<0.05). The expression of all genes examined differed significantly between the three localizations in the heart. miR-21 and miR-133a were differently expressed among the experimental groups (P<0.05). CONCLUSIONS Plasma proANP and SDMA levels and tissue expression of miR-21 and miR-133a are associated with severity of chronic MR in an experimental porcine model.
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Affiliation(s)
| | | | - Nora E Zois
- Department of Clinical BiochemistryCopenhagen University Hospital RigshospitaletCopenhagenDenmark
| | - Nathja Ravn
- Department of Cardiothoracic and Vascular SurgeryAarhus University HospitalAarhusDenmark
| | - Jens P Goetze
- Department of Clinical BiochemistryCopenhagen University Hospital RigshospitaletCopenhagenDenmark
- Department of Clinical BiochemistryAarhus University HospitalAarhusDenmark
| | - Signe E Cremer
- Department of Veterinary Disease Biology, Faculty of Health and Medical SciencesUniversity of CopenhagenFrederiksberg CDenmark
| | - Tom Teerlink
- Department of Clinical ChemistryVU University Medical CenterAmsterdamThe Netherlands
| | - Páll S Leifsson
- Department of Veterinary Disease Biology, Faculty of Health and Medical SciencesUniversity of CopenhagenFrederiksberg CDenmark
| | - Jesper L Honge
- Department of Cardiothoracic and Vascular SurgeryAarhus University HospitalAarhusDenmark
| | - J Michael Hasenkam
- Department of Cardiothoracic and Vascular SurgeryAarhus University HospitalAarhusDenmark
| | - Lisbeth H Olsen
- Department of Veterinary Disease Biology, Faculty of Health and Medical SciencesUniversity of CopenhagenFrederiksberg CDenmark
- Correspondence should be addressed to L H Olsen
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Zois NE, Tidholm A, Nägga KM, Moesgaard SG, Rasmussen CE, Falk T, Häggström J, Pedersen HD, Åblad B, Nilsen HY, Olsen LH. Radial and longitudinal strain and strain rate assessed by speckle-tracking echocardiography in dogs with myxomatous mitral valve disease. J Vet Intern Med 2012; 26:1309-19. [PMID: 23113772 DOI: 10.1111/j.1939-1676.2012.01017.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2011] [Revised: 07/25/2012] [Accepted: 09/05/2012] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND Assessment of left ventricular (LV) function using conventional echocardiographic methods is difficult in mitral regurgitation (MR) owing to altered hemodynamic loading conditions. Newer methods such as speckle-tracking echocardiography (STE) provide assessment of LV strain (St) and strain rates (SR). HYPOTHESES Global St and SR are 1) decreased in dogs with clinical signs of congestive heart failure (CHF) due to myxomatous mitral valve disease (MMVD) compared with clinically healthy dogs, and are 2) associated with conventional echocardiographic indices of MMVD severity. ANIMALS The study subjects were 93 privately owned dogs with different MMVD severities. METHODS Prospectively recruited dogs were grouped according to MMVD severity based on echocardiographic evaluation of MR and presence of clinical signs. Global radial and longitudinal St, SR, and indices of LV dyssynchrony were assessed. RESULTS On group-wise comparisons, dogs with CHF had increased global longitudinal St, global longitudinal and radial SR in systole (SRs), and early diastole (SRe) compared with dogs with no or minimal MR (all P < .04). On multiple regression analyses, these global STE variables increased with degree of MR, but associations with left atrial-to-aortic root ratio (LA/Ao) were best described by second-order polynomial equations. Thus, curvilinear relationships were found for LA/Ao and longitudinal St, SRs, and SRe (all P < .002) and radial St and SRe (all P < .001). CONCLUSIONS AND CLINICAL IMPORTANCE Assessed by STE, LV function appeared to be augmented in moderate-to-severe disease. However, at CHF stages with greatly enlarged atria, a decrease to levels comparable to dogs with no or minimal MR was observed.
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Affiliation(s)
- N E Zois
- Department of Veterinary Clinical and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark.
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15
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Rasmussen CE, Falk T, Zois NE, Moesgaard SG, Häggström J, Pedersen HD, Ablad B, Nilsen HY, Olsen LH. Heart rate, heart rate variability, and arrhythmias in dogs with myxomatous mitral valve disease. J Vet Intern Med 2011; 26:76-84. [PMID: 22151356 DOI: 10.1111/j.1939-1676.2011.00842.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2011] [Revised: 08/29/2011] [Accepted: 10/05/2011] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND Autonomic modulation of heart rhythm is thought to influence the pathophysiology of myxomatous mitral valve disease (MMVD). HYPOTHESES (1) Holter-derived variables reflecting autonomic modulation of heart rhythm change with MMVD severity in Cavalier King Charles Spaniels (CKCS); (2) Holter-derived variables can identify MMVD severity in CKCS; and (3) Holter-derived variables in CKCS in congestive heart failure (CHF) secondary to MMVD differ from those in dogs of other breeds in CHF. ANIMALS Ninety privately owned dogs: 70 CKCS with variable MMVD severity and 20 non-CKCS in CHF secondary to MMVD. METHODS Dogs were prospectively recruited and divided into 5 MMVD severity groups based on history, breed, and physical and echocardiographic examination findings. Holter-derived variables included heart rate variability (HRV), heart rate (HR), and arrhythmia evaluated from 24-hour Holter recordings. RESULTS In CKCS, 18 of 26 HRV (all P < .0002) and 3 of 9 arrhythmia (all P < .0004) variables decreased with increasing MMVD, whereas minimum and mean HR (all P < .0001) increased with increasing MMVD severity. An arrhythmia variable representing sinus arrhythmia ("premature normals") (P < .0001) and the HRV variable triangular index (TI) (P < .0001) could distinguish CKCS with moderate or severe mitral regurgitation from CKCS in CHF in specific intervals. Among dogs in CHF, Holter-derived variables did not differ among breeds. CONCLUSIONS AND CLINICAL IMPORTANCE In CKCS, Holter-derived variables changed with MMVD severity. "Premature normals" and TI showed diagnostic potential. Breed differences were not seen among dogs in CHF secondary to MMVD.
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Affiliation(s)
- C E Rasmussen
- Department of Basic Animal and Veterinary Sciences, University of Copenhagen, Frederiksberg, Denmark.
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16
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Rasmussen CE, Vesterholm S, Ludvigsen TP, Häggström J, Pedersen HD, Moesgaard SG, Olsen LH. Holter monitoring in clinically healthy Cavalier King Charles Spaniels, Wire-haired Dachshunds, and Cairn Terriers. J Vet Intern Med 2011; 25:460-8. [PMID: 21418322 DOI: 10.1111/j.1939-1676.2011.0707.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND Few reported studies describe normal values from 24-hour ECG (Holter) recordings of small breed dogs. OBJECTIVES To investigate influence of breed, age, sex, body weight, degree of recording artifact, and mitral valve prolapse (MVP) on Holter recordings of 3 breeds of small dogs that have differing predispositions for myxomatous mitral valve disease. The study also assessed if heart rate (HR) at clinical examination (HRex) was associated with HR during Holter monitoring and evaluated the reproducibility of Holter variables. ANIMALS Fifty clinically healthy, privately owned dogs of the breeds Cavalier King Charles Spaniel (CKCS), Wire-haired Dachshund (wD), or Cairn Terrier (CT). METHODS Prospective, longitudinal observational study. Dogs were recruited for clinical examination, echocardiography, and Holter monitoring. In 8 CKCS, Holter recordings were performed twice with a 7-day interval. Arrhythmia and heart rate variability (HRV) analysis (time and frequency domain analysis) were performed on Holter recordings. RESULTS Fifteen out of 27 Holter derived variables were significantly associated with breed (P < .03), but not with age (P > .7), sex (P > .2), body weight (P > .7), degree of recording artifact (P > .4), or MVP (P > .6). During Holter recording, minimum (P = .0001) and mean HR (P = .0001) were higher in CKCS compared with wD. CKCS had significantly lower values than wD, CT, or both in 10 out of 13 HRV variables (P < .03). Minimum and mean HR during Holter recording were correlated with HRex (r = 0.55, P = .0003). HR and time domain variables had a coefficient of variation <10%. CONCLUSIONS AND CLINICAL IMPORTANCE There is an influence of breed on Holter-derived variables in 3 breeds of small dogs. Arrhythmia and HRV analysis can be performed on 24-hour ambulatory ECG (Holter) recordings. Arrhythmia analysis includes HR measurements and identification of arrhythmias.
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Affiliation(s)
- C E Rasmussen
- Department of Basic Animal and Veterinary Sciences, Faculty of Life Sciences, University of Copenhagen, Frederiksberg, Denmark.
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Moesgaard SG, Falk T, Teerlink T, Guðmundsdóttir HH, Sigurðardóttir S, Rasmussen CE, Olsen LH. Brain-natriuretic peptide and cyclic guanosine monophosphate as biomarkers of myxomatous mitral valve disease in dogs. Vet J 2010; 189:349-52. [PMID: 20822939 DOI: 10.1016/j.tvjl.2010.07.019] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2009] [Revised: 07/13/2010] [Accepted: 07/27/2010] [Indexed: 11/24/2022]
Abstract
Elevations in the plasma concentrations of natriuretic peptides correlate with increased severity of myxomatous mitral valve disease (MMVD) in dogs. This study correlates the severity of MMVD with the plasma concentrations of the biomarkers N-terminal fragment of the pro-brain-natriuretic peptide (NT-proBNP) and its second messenger, cyclic guanosine monophosphate (cGMP). Furthermore, the L-arginine:asymmetric dimethylarginine (ADMA) ratio was measured as an index of nitric oxide availability. The study included 75 dogs sub-divided into five groups based on severity of MMVD as assessed by clinical examination and echocardiography. Plasma NT-proBNP and cGMP concentrations increased with increasing valve dysfunction and were significantly elevated in dogs with heart failure. The cGMP:NT-proBNP ratio decreased significantly in dogs with heart failure, suggesting the development of natriuretic peptide resistance. Although the l-arginine:ADMA ratio decreased with increasingly severe MMVD, this was largely due to the older age of the dogs with heart failure.
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Affiliation(s)
- Sophia G Moesgaard
- Department of Basic Animal and Veterinary Sciences, The Faculty of Life Sciences, University of Copenhagen, Denmark.
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Tarnow I, Olsen LH, Kvart C, Hoglund K, Moesgaard SG, Kamstrup TS, Pedersen HD, Häggström J. Predictive value of natriuretic peptides in dogs with mitral valve disease. Vet J 2009; 180:195-201. [DOI: 10.1016/j.tvjl.2007.12.026] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2007] [Revised: 12/04/2007] [Accepted: 12/05/2007] [Indexed: 10/21/2022]
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Moesgaard SG, Holte AV, Mogensen T, Mølbak J, Kristensen AT, Jensen AL, Teerlink T, Reynolds AJ, Olsen LH. Effects of breed, gender, exercise and white-coat effect on markers of endothelial function in dogs. Res Vet Sci 2007; 82:409-15. [PMID: 17092526 DOI: 10.1016/j.rvsc.2006.09.003] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2006] [Revised: 09/15/2006] [Accepted: 09/17/2006] [Indexed: 12/21/2022]
Abstract
This study examines how systemic biomarkers of endothelial function and nitric oxide metabolism are affected by exercise in dogs. Furthermore, breed variation and white-coat effect have been tested by sampling three different dog breeds both in their home and in a clinical setting. Short-term exercise increased plasma nitrate and nitrite (NOx) and von Willebrand factor (vWf). There was significant difference between Pointers and the small dog breeds Cairn Terriers and Cavalier King Charles Spaniels in the general plasma levels of vWf and asymmetric dimethylarginine (ADMA). NOx and vWf were significantly higher when the sample was taken in the laboratory cf. at home, whereas ADMA and L-arginine were significantly lower. In conclusion, both short-term exercise and white-coat effect influence several plasma markers of endothelial function depending also on the breed and gender of the dogs. These findings should be considered in future studies concerning endothelial function in dogs.
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Affiliation(s)
- S G Moesgaard
- Department of Basic Animal and Veterinary Sciences, The Royal Veterinary and Agricultural University, 7 Groennegaardsvej, Frederiksberg C DK-1870, Denmark.
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Pedersen LG, Offenberg H, Moesgaard SG, Thomsen PD, Pedersen HD, Olsen LH. Transcription levels of endothelin-1 and endothelin receptors are associated with age and leaflet location in porcine mitral valves. ACTA ACUST UNITED AC 2007; 54:113-8. [PMID: 17381672 DOI: 10.1111/j.1439-0442.2007.00894.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The aim of the study was to investigate the expression levels of endothelin-1 (ET-1) and ET(A) and ET(B) receptors (ET(A)-R and ET(B)-R) in porcine mitral valves and associate the transcription levels to age, leaflet location and deposition of mucopolysaccharides (MPS). Tissue samples from the chordal and inter-chordal insertion area of the anterior mitral valve leaflet from 11 sows (> or = 2 years of age) and 10 slaughter pigs (approximately 6 months old) were obtained and the relative gene expression levels of ET-1, ET(A)-R and ET(B)-R measured by semi-quantitative real-time PCR. A separate tissue sample was taken for histopathological grading of MPS deposition. The transcription levels of ET-1 (P < 0.0001) and ET(A)-R (P < 0.0004) were significantly higher in leaflets from the sows compared with slaughter pigs. The gene expression of ET(B)-R was not associated to age (P = 0.38), but increased in chordal insertion areas compared with inter-chordal areas (P = 0.01). The expression of ET-1 and ET(A)-R mRNA did not differ significantly between the two leaflet locations. The valve leaflets from sows had a significantly increased degree of MPS deposition compared with slaughter pigs upon histological examination (P = 0.04). In conclusion, an age-related valvular degeneration is observed in porcine mitral valve leaflets and ET-1 is suggested to be involved through action of both ET(A) and ET(B) receptors.
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Affiliation(s)
- L G Pedersen
- Department of Basic Animal and Veterinary Sciences, The Royal Vetinary and Agricultural University, Copenhagen, Denmark
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Moesgaard SG, Olsen LH, Aasted B, Viuff BM, Pedersen LG, Pedersen HD, Harrison AP. Direct measurements of nitric oxide release in relation to expression of endothelial nitric oxide synthase in isolated porcine mitral valves. ACTA ACUST UNITED AC 2007; 54:156-60. [PMID: 17381681 DOI: 10.1111/j.1439-0442.2007.00915.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The aim of this study was to measure the direct release of nitric oxide (NO) from the porcine mitral valve using a NO microelectrode. Furthermore, the expression and localization of endothelial nitric oxide synthase (eNOS) in the mitral valve was studied using immunohistochemistry, Western blotting and RT-PCR. Results show that bradykinin increases NO release from mitral valves (DeltaBradykinin: 33.71 +/- 10.41 nm NO, P < 0.001, n = 10), whereas N-nitro-l-arginine methyl esther (l-NAME) decreases NO release when compared with basal level (Deltal-NAME: 82.69 +/- 15.66 nm NO, P < 0.005, n = 4). Both protein and mRNA expression of eNOS in mitral valves and in isolated valvular endothelial cells suggest that the NO release is mainly associated with the mitral valve endothelium. It is concluded that direct NO release from porcine mitral valves coincides with eNOS expression. This study documents useful techniques for investigations into the role of local NO release in mitral valve diseases.
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Affiliation(s)
- S G Moesgaard
- Department of Basic Animal and Veterinary Sciences, The Royal Vetinary and Agricultural University, Fredriksberg, Denmark.
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Moesgaard SG, Olsen LH, Viuff BM, Baandrup U, Pedersen LG, Thomsen PD, Pedersen HD, Harrison AP. Increased nitric oxide release and expression of endothelial and inducible nitric oxide synthases in mildly changed porcine mitral valve leaflets. J Heart Valve Dis 2007; 16:67-75. [PMID: 17315385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
BACKGROUND AND AIM OF THE STUDY Little is known of the local role of nitric oxide (NO) in heart valves in relation to heart valve diseases. The study aim was to examine NO release and the expression of both endothelial nitric oxide synthase (eNOS) and inducible nitric oxide synthase (iNOS) in relation to early local changes in porcine mitral valves. METHODS A histological evaluation of mitral valve leaflets from slaughter pigs and sows was made, and the expression of eNOS and iNOS protein measured using immunohistochemistry. Furthermore, mRNA levels of eNOS and iNOS were measured using real-time RT-PCR. A calibrated NO-specific electrode was used to measure local NO release in specific regions of the anterior mitral leaflet from slaughter pigs and sows interchordally at the tip of the leaflet (region A), at the chordal insertion (region B), and at the center of the leaflet (region C). RESULTS Leaflets from sows had an increased accumulation of mucopolysaccharides (MPS) compared to those from slaughter pigs. Furthermore, mRNA levels of eNOS and iNOS were significantly increased in region C due to very high levels of expression in some sow leaflets. NO release in the sow mitral valve leaflet was increased in regions B and C compared to that in region A. CONCLUSION The relative distribution of NO release is increased in regions of porcine mitral valve leaflets with deposition of MPS and defraction of the valve structure, which may reflect changes in both eNOS and iNOS expression.
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Affiliation(s)
- Sophia G Moesgaard
- Department of Basic Animal and Veterinary Sciences, The Royal Veterinary and Agricultural University, 7 Groennegaardsvej, 1870 Frederiksberg, Denmark.
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Moesgaard SG, Brand CL, Sturis J, Ahrén B, Wilken M, Fleckner J, Carr RD, Svendsen O, Hansen AJ, Gram DX. Sensory nerve inactivation by resiniferatoxin improves insulin sensitivity in male obese Zucker rats. Am J Physiol Endocrinol Metab 2005; 288:E1137-45. [PMID: 15883192 DOI: 10.1152/ajpendo.00356.2004] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Recent studies have suggested that sensory nerves may influence insulin secretion and action. The present study investigated the effects of resiniferatoxin (RTX) inactivation of sensory nerves (desensitization) on oral glucose tolerance, insulin secretion and whole body insulin sensitivity in the glucose intolerant, hyperinsulinemic, and insulin-resistant obese Zucker rat. After RTX treatment (0.05 mg/kg RTX sc given at ages 8, 10, and 12 wk), fasting plasma insulin was reduced (P < 0.0005), and oral glucose tolerance was improved (P < 0.005). Pancreas perfusion showed that baseline insulin secretion (7 mM glucose) was lower in RTX-treated rats (P = 0.01). Insulin secretory responsiveness to 20 mM glucose was enhanced in the perfused pancreas of RTX-treated rats (P < 0.005) but unaffected in stimulated, isolated pancreatic islets. At the peak of spontaneous insulin resistance in the obese Zucker rat, insulin sensitivity was substantially improved after RTX treatment, as evidenced by higher glucose infusion rates (GIR) required to maintain euglycemia during a hyperinsulinemic euglycemic (5 mU.kg(-1).min(-1)) clamp (GIR(60-120min): 5.97 +/- 0.62 vs. 11.65 +/- 0.83 mg.kg(-1).min(-1) in RTX-treated rats, P = 0.003). In conclusion, RTX treatment and, hence, sensory nerve desensitization of adult male obese Zucker rats improved oral glucose tolerance by enhancing insulin secretion, and, in particular, by improving insulin sensitivity.
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Moesgaard SG, Ahrén B, Carr RD, Gram DX, Brand CL, Sundler F. Effects of high-fat feeding and fasting on ghrelin expression in the mouse stomach. ACTA ACUST UNITED AC 2005; 120:261-7. [PMID: 15177945 DOI: 10.1016/j.regpep.2004.03.018] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2003] [Revised: 03/18/2004] [Accepted: 03/26/2004] [Indexed: 10/26/2022]
Abstract
Ghrelin is a peptide identified as an endogenous ligand for the growth hormone secretagogue receptor. Studies have shown that ghrelin stimulates growth hormone, promotes food intake and decreases energy expenditure. Furthermore, feeding status seems to influence plasma ghrelin levels, as these are increased during fasting, whereas feeding and oral glucose intake reduce plasma ghrelin. This study examined whether standardized obesity and fasting affect cellular expression of ghrelin. Specimens from the gastrointestinal tract of fed or 18-h fasted, low-fat or high-fat fed (10 weeks on diet) C57BL/6J mice were studied by immunocytochemistry (ICC) for ghrelin and in situ hybridization (ISH) for ghrelin mRNA. Ghrelin was expressed in especially the corpus but also the antrum of the stomach of all groups studied. Cells positive for ghrelin and ghrelin mRNA in the stomach were reduced in high-fat fed mice. In contrast, ghrelin expression was not affected by fasting. The reduction in ghrelin expression in the high-fat fed mice was associated with a reduction in plasma levels of ghrelin, whereas after fasting, when expression rate was not altered, there was an increase in plasma ghrelin. In conclusion, ghrelin is highly expressed in the corpus and antrum of the stomach of C57BL/6J mice. This expression is reduced in obesity, whereas fasting has no effect.
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