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Bredum SK, Strathe AV, Jacobsen J, Christoffersen BØ, Gehre M, Kümmel S, Junghans P, Marcussen C. Quantifying energy expenditure in Göttingen Minipigs with the 13C-bicarbonate method under basal and drug-treated conditions. Clin Nutr ESPEN 2023; 58:388-396. [PMID: 38057031 DOI: 10.1016/j.clnesp.2023.10.041] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 10/25/2023] [Accepted: 10/30/2023] [Indexed: 12/08/2023]
Abstract
Effective treatments of obesity focusing on energy expenditure (EE) are needed. To evaluate future EE-modulating drug candidates, appropriate animal models and methods to assess EE are needed. This study aimed to evaluate the stable isotope 13C-bicarbonate method (13C-BM) for estimating EE in Göttingen minipigs under basal and drug-treated conditions. Four experiments (Expt.1-4) were conducted to assess: 1) the 13C-BM reproducibility using breath sample collection (n = 8), on two consecutive days, 2) the effect of two dose levels (5 and 10 mg/kg body weight (BW)) of the mitochondrial uncoupler dinitrophenol (DNP) in a crossover design (n = 8), 3) sampling method agreement; blood vs. exhaled air (n = 6) and 4) 13C-BM using constant isotope infusion compared with indirect calorimetry (IC) (n = 3). Results correlated significantly (p < 0.001) between days (Expt.1), with an average coefficient of variance of 5.4 ± 2.3%. Administration of 10 mg DNP/kg BW increased (p < 0.01) EE by 33.2 ± 6.4% (Expt.2). Results based on different sampling methods correlated significantly (p < 0.001) and EE increased after 10 mg DNP/kg BW (p < 0.05) in Expt.3. However, results based on blood sampling were significantly higher (p < 0.01) than those of exhaled air. No effect of DNP and significantly different EE results (p < 0.05) was observed in a limited number of animals, when constant isotope infusion and blood sampling was compared with IC (Expt.4). In conclusion, the 13C-BM is useful for investigating treatment effects on EE in minipigs. However, further validation under standardized conditions is needed to provide accurate estimates of the 13C recovery factor and respiratory quotient, both of decisive importance when using the 13C-BM.
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Affiliation(s)
- Simon K Bredum
- Department of Veterinary and Animal Sciences, University of Copenhagen, Denmark
| | - Anja V Strathe
- Department of Veterinary and Animal Sciences, University of Copenhagen, Denmark
| | | | | | - Matthias Gehre
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research, Leipzig, Germany
| | - Steffen Kümmel
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research, Leipzig, Germany
| | - Peter Junghans
- Research Institute for Farm Animal Biology (FBN), Institute of Nutritional Physiology 'Oskar Kellner', Dummerstorf, Germany
| | - Caroline Marcussen
- Department of Veterinary and Animal Sciences, University of Copenhagen, Denmark.
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2
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Christoffersen BØ, Bundgaard CJ, Hjøllund KR, Fels JJ, Boll KK, Lyhne MK, Olsen LH. Influence of general anaesthesia on circulating biomarkers of glucose metabolism in pigs. Lab Anim 2023; 57:650-663. [PMID: 37647768 DOI: 10.1177/00236772231187179] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Abstract
Pigs are widely used in metabolic research with procedures often requiring general anaesthesia. The aim was to investigate the effect of four different anaesthetic protocols: 1) isoflurane inhalation, 2) propofol infusion, 3) a mixture of tiletamine, zolazepam, medetomidine, ketamine and butorphanol (TZMKB)) and 4) ketamine combined with midazolam and xylazine (KMX)) on selected biomarkers during basal and glucose stimulated conditions. Eight domestic pigs were included in a cross-over design. Plasma concentrations of glucose, insulin, C-peptide, glucagon, cortisol, triglycerides, total cholesterol, aspartate amino transferase and alanine amino transferase, creatinine, urea, fructosamine, albumin, free fatty acids (FFAs) and glycerol were measured at baseline, during 2 h of anaesthesia and during 1 h of recovery. Intravenous glucose tolerance test (IVGTT, 0.5 g glucose/kg) was performed after 1 h of anaesthesia. Glucose disappearance rate and areas under the insulin, C-peptide and glucagon curves from the IVGTT were calculated. All four anaesthetic protocols affected glucose metabolism parameters significantly compared with un-anaesthetised pigs, which was particularly evident during IVGTT and for TZMKB and KMX anaesthesia. Propofol additionally influenced the plasma concentrations of triglycerides, FFAs and glycerol significantly. The remaining circulating biomarkers were largely unaffected by anaesthesia. These data underline the importance of considering the anaesthetic protocol in porcine studies of circulating metabolic biomarkers.
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Affiliation(s)
| | | | | | | | - Kirstine K Boll
- Department of Veterinary and Animal Sciences, University of Copenhagen, Denmark
| | - Mille K Lyhne
- Novo Nordisk A/S, Maaloev, Denmark
- Department of Veterinary and Animal Sciences, University of Copenhagen, Denmark
| | - Lisbeth H Olsen
- Department of Veterinary and Animal Sciences, University of Copenhagen, Denmark
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Lützhøft DO, Sinioja T, Christoffersen BØ, Jakobsen RR, Geng D, Ahmad HFB, Straarup EM, Pedersen KM, Kot W, Pedersen HD, Cirera S, Hyötyläinen T, Nielsen DS, Hansen AK. Marked gut microbiota dysbiosis and increased imidazole propionate are associated with a NASH Göttingen Minipig model. BMC Microbiol 2022; 22:287. [DOI: 10.1186/s12866-022-02704-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Accepted: 11/11/2022] [Indexed: 12/03/2022] Open
Abstract
Abstract
Background
Gut microbiota dysbiosis is associated with the development of non-alcoholic steatohepatitis (NASH) through modulation of gut barrier, inflammation, lipid metabolism, bile acid signaling and short-chain fatty acid production. The aim of this study was to describe the impact of a choline-deficient amino acid defined high fat diet (CDAHFD) on the gut microbiota in a male Göttingen Minipig model and on selected pathways implicated in the development of NASH.
Results
Eight weeks of CDAHFD resulted in a significantly altered colon microbiota mainly driven by the bacterial families Lachnospiraceae and Enterobacteriaceae, being decreased and increased in relative abundance, respectively. Metabolomics analysis revealed that CDAHFD decreased colon content of short-chain fatty acid and increased colonic pH. In addition, serum levels of the microbially produced metabolite imidazole propionate were significantly elevated as a consequence of CDAHFD feeding. Hepatic gene expression analysis showed upregulation of mechanistic target of rapamycin (mTOR) and Ras Homolog, MTORC1 binding in addition to downregulation of insulin receptor substrate 1, insulin receptor substrate 2 and the glucagon receptor in CDAHFD fed minipigs. Further, the consequences of CDAHFD feeding were associated with increased levels of circulating cholesterol, bile acids, and glucagon but not total amino acids.
Conclusions
Our results indicate imidazole propionate as a new potentially relevant factor in relation to NASH and discuss the possible implication of gut microbiota dysbiosis in the development of NASH. In addition, the study emphasizes the need for considering the gut microbiota and its products when developing translational animal models for NASH.
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Feng Y, Cirera S, Taşöz E, Liu Y, Olsen LH, Christoffersen BØ, Pedersen HD, Ludvigsen TP, Kirk RK, Schumacher-Petersen C, Deng Y, Fredholm M, Gao F. Diet-Dependent Changes of the DNA Methylome Using a Göttingen Minipig Model for Obesity. Front Genet 2021; 12:632859. [PMID: 33777102 PMCID: PMC7991730 DOI: 10.3389/fgene.2021.632859] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [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: 11/24/2020] [Accepted: 02/15/2021] [Indexed: 12/12/2022] Open
Abstract
Objective: Environmental factors can influence obesity by epigenetic mechanisms. The aim of this study was to investigate obesity-related epigenetic changes and the potential for reversal of these changes in the liver of Göttingen minipigs subjected to diet interventions. Methods: High-throughput liquid hybridization capture-based bisulfite sequencing (LHC-BS) was used to quantify the methylation status of gene promotor regions in liver tissue in three groups of male castrated Göttingen minipigs: a standard chow group (SD, N = 7); a group fed high fat/fructose/cholesterol diet (FFC, N = 10) and a group fed high fat/fructose/cholesterol diet during 7 months and reversed to standard diet for 6 months (FFC/SD, N = 12). Expression profiling by qPCR of selected metabolically relevant genes was performed in liver tissue from all pigs. Results: The pigs in the FFC diet group became morbidly obese. The FFC/SD diet did not result in a complete reversal of the body weight to the same weight as in the SD group, but it resulted in reversal of all lipid related metabolic parameters. Here we identified widespread differences in the patterning of cytosine methylation of promoters between the different feeding groups. By combining detection of differentially methylated genes with a rank-based hypergeometric overlap algorithm, we identified 160 genes showing differential methylation in corresponding promoter regions in the FFC diet group when comparing with both the SD and FFC/SD groups. As expected, this differential methylation under FFC diet intervention induced de-regulation of several metabolically-related genes involved in lipid/cholesterol metabolism, inflammatory response and fibrosis generation. Moreover, five genes, of which one is a fibrosis-related gene (MMP9), were still perturbed after diet reversion. Conclusion: Our findings highlight the potential of exploring diet-epigenome interactions for treatment of obesity.
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Affiliation(s)
- Y Feng
- Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China.,Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, China
| | - S Cirera
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - E Taşöz
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Y Liu
- Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
| | - L H Olsen
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark
| | | | - H D Pedersen
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark.,Global Drug Discovery, Novo Nordisk A/S, Måløv, Denmark.,Medical Evaluation & Biostatistics, Danish Medicines Agency, Copenhagen, Denmark
| | - T P Ludvigsen
- Global Drug Discovery, Novo Nordisk A/S, Måløv, Denmark
| | - R K Kirk
- Global Drug Discovery, Novo Nordisk A/S, Måløv, Denmark
| | - C Schumacher-Petersen
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark.,Global Drug Discovery, Novo Nordisk A/S, Måløv, Denmark
| | - Y Deng
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, China
| | - M Fredholm
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - F Gao
- Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China.,Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark
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Pedersen HD, Galsgaard ED, Christoffersen BØ, Cirera S, Holst D, Fredholm M, Latta M. NASH-inducing Diets in Göttingen Minipigs. J Clin Exp Hepatol 2020; 10:211-221. [PMID: 32405177 PMCID: PMC7212300 DOI: 10.1016/j.jceh.2019.09.004] [Citation(s) in RCA: 9] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Accepted: 09/15/2019] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Owing to the human-like physiology, a minipig model of nonalcoholic steatohepatitis (NASH) could be valuable. Pigs, however, rarely develop substantial hepatic steatosis, even when fed diets with high fat, fructose, and cholesterol (FFC) content. The potential of choline-deficient, amino acid-defined high-fat diets (CDAHFD) was therefore evaluated in Göttingen Minipigs. METHODS Castrated male Göttingen Minipigs were fed either chow (n = 5) or one of the three NASH diets: FFC (n = 5), CDAHFD with sucrose (CDAHFD-S; n = 4), or fructose (CDAHFD-F; n = 4) for 8 weeks. Liver and blood samples were collected after 2 weeks and at termination. RESULTS Compared with chow, the body weight was higher after FFC (9.8 ± 0.4 versus 8.5 ± 1.2 kg; mean ± SD) and less after CDAHFD-S (6.4 ± 0.8 kg) and CDAHFD-F (6.9 ± 0.8 kg). Liver weight per kg body weight was significantly increased in all 3 NASH groups (FFC 2.1 times; and both CDAHFD diets 3.1 times). Histologically, pronounced macrovesicular steatosis developed only in the CDAHFD groups. Inflammation was present in all three NASH groups. In the CDAHFD groups, inflammatory cells formed crown-like structures around steatotic hepatocytes. Sirius red staining revealed mild fibrosis in the two CDAHFD groups with the fibrotic potential being further supported by immunohistochemical staining for activated stellate cells and gene expression analyses. No noticeable differences were found between CDAHFD-S and CDAHFD-F. CONCLUSIONS Göttingen Minipigs fed CDAHFD developed pronounced steatosis with inflammation around steatotic hepatocytes and incipient fibrosis, thereby showing potential as a model for human NASH. Further studies are needed to investigate the period needed for marked fibrosis to develop.
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Key Words
- -F, with fructose)
- ALP, alkaline phosphatase
- ALT, alanine transaminase
- AST, aspartate transaminase
- Animal model
- CD45, cluster of differentiation 45
- CDAHFD, choline-deficient
- Choline
- EDTA, ethylenediaminetetraacetic acid
- FFC, high-fat, fructose, cholesterol
- Fatty liver
- Fibrosis
- GGT, gamma-glutamyltransferase
- GLDH, glutamate dehydrogenase
- HE, hematoxylin and eosin
- NAFLD, non-alcoholic fatty liver disease
- NASH, non-alcoholic steatohepatitis
- Porcine
- SMA, smooth muscle actin
- amino acid defined high-fat diet (-S, with sucrose
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Affiliation(s)
- Henrik D. Pedersen
- Ellegaard Göttingen Minipigs A/S, Dalmose, Denmark,Department of Veterinary and Animal Sciences, University of Copenhagen, Denmark,Address for correspondence: Henrik D. Pedersen, Ellegaard Göttingen Minipigs A/S, Soroe Landevej 302, 4261 Dalmose, Denmark.
| | | | | | - Susanna Cirera
- Department of Veterinary and Animal Sciences, University of Copenhagen, Denmark
| | - Dorte Holst
- Global Drug Discovery, Novo Nordisk A/S, Maaloev, Denmark
| | - Merete Fredholm
- Department of Veterinary and Animal Sciences, University of Copenhagen, Denmark
| | - Markus Latta
- Global Drug Discovery, Novo Nordisk A/S, Maaloev, Denmark
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6
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Viuff BM, Straarup EM, Nowak J, Morgills L, Skydsgaard M, Sjögren I, Wulff BS, Christoffersen BØ. Lipid Embolism in Obese Göttingen Minipigs. Toxicol Pathol 2019; 48:379-392. [DOI: 10.1177/0192623319880464] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Pigs are used as a model of human obesity, both for metabolic characterization and for evaluation of pharmacological interventions. Over a period of 7 years, acute death or clinical signs requiring immediate euthanasia were observed in 12 obese Göttingen minipigs (GMs) included in different pharmacological studies. The GM were fed ad libitum on normal chow-diet and the unscheduled deaths occurred in animals treated with drug candidates as well as in untreated animals. The most prominent clinical signs requiring euthanasia included varying degrees of respiratory distress; and on histopathological examination, thickening of the alveolar septa due to vacuolation was observed throughout the lung in 10 of the 12 animals. Furthermore, vacuolation in glomeruli of the kidney was detected in 9 of the 10 animals. Oil red O staining of cryosections demonstrated that the vacuoles both in lung and kidney contained lipid, and immunohistochemistry with anti-von Willebrand factor and transmission electron microscopy revealed that the lipid was localized in the lumen of blood vessels establishing the occurrence of fatal pulmonary lipid embolism. Additionally, lipogranulomatous inflammation in the abdominal adipose tissue was observed in all the GMs with lipid emboli.
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Affiliation(s)
| | | | - Jette Nowak
- Global Drug Discovery, Novo Nordisk A/S, Måløv, Denmark
| | - Line Morgills
- CitoxLAB Denmark (A Charles River Company), Lille Skensved, Denmark
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7
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Christoffersen BØ, Skyggebjerg RB, Bugge A, Kirk RK, Vestergaard B, Uldam HK, Fels JJ, Pyke C, Sensfuss U, Sanfridson A, Clausen TR. Long-acting CCK analogue NN9056 lowers food intake and body weight in obese Göttingen Minipigs. Int J Obes (Lond) 2019; 44:447-456. [PMID: 31175319 PMCID: PMC6997118 DOI: 10.1038/s41366-019-0386-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/03/2018] [Revised: 03/16/2019] [Accepted: 04/05/2019] [Indexed: 12/18/2022]
Abstract
Background/Objectives Cholecystokinin (CCK) is a regulator of appetite and energy intake in man. The aim of this study was to determine the effect of NN9056, a long-acting CCK-1 receptor-selective CCK analogue, on food intake and body weight (BW) in obese Göttingen Minipigs. Subjects/Methods Tolerability of NN9056 and acute effects on food intake, pancreas histology, amylase and lipase levels were assessed in lean domestic pigs in doses up to 100 nmol/kg (n = 3–4). Subsequently, obese Göttingen Minipigs were treated subcutaneously (s.c.) once daily for 13 weeks with vehicle, NN9056 low dose (regulated from 5 to 2 nmol/kg) or NN9056 high dose (10 nmol/kg) (n = 7–8). Food intake was measured daily and BW twice weekly. At the end of the treatment period, an intravenous glucose tolerance test (IVGTT) and a 24-h exposure profile was obtained. Data are mean ± SD. Results The acute studies in domestic pigs showed significant and dose-dependent effect of NN9056 on food intake, acceptable tolerability and no histopathological signs of pancreatitis. Sub-chronic treatment in obese Göttingen Minipigs was also well tolerated and accumulated food intake was significantly lower in both treated groups compared to vehicle, with no significant difference between the dose levels of NN9056 (41.8 ± 12.6, 51.5 ± 13.8 and 86.5 ± 19.5 kg in high-dose, low-dose and vehicle groups, respectively, p = 0.012 and p < 0.0001 for low and high dose vs. vehicle, respectively). Accordingly, there was a weight loss in both treated groups vs. a weight gain in the vehicle group (−7.2 ± 4.6%, −2.3 ± 3.2% and 12.3 ± 3.9% in the high-dose, low-dose and vehicle groups, respectively, p < 0.0001 for both vs. vehicle). IVGTT data were not significantly different between groups. Conclusion NN9056, a long-acting CCK-1 receptor-selective CCK analogue, significantly reduced food intake and BW in obese Göttingen Minipigs after once daily s.c. dosing for 13 weeks.
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Affiliation(s)
| | | | - Anne Bugge
- Global Drug Discovery, Novo Nordisk A/S, Novo Nordisk Park, 2760, Måløv, Denmark
| | - Rikke Kaae Kirk
- Global Drug Discovery, Novo Nordisk A/S, Novo Nordisk Park, 2760, Måløv, Denmark
| | - Bill Vestergaard
- Global Drug Discovery, Novo Nordisk A/S, Novo Nordisk Park, 2760, Måløv, Denmark
| | - Henriette Kold Uldam
- Global Research Technologies, Novo Nordisk A/S, Novo Nordisk Park, 2760, Måløv, Denmark
| | - Johannes Josef Fels
- Global Research Technologies, Novo Nordisk A/S, Novo Nordisk Park, 2760, Måløv, Denmark
| | - Charles Pyke
- Global Drug Discovery, Novo Nordisk A/S, Novo Nordisk Park, 2760, Måløv, Denmark
| | - Ulrich Sensfuss
- Global Research Technologies, Novo Nordisk A/S, Novo Nordisk Park, 2760, Måløv, Denmark
| | - Annika Sanfridson
- Global Drug Discovery, Novo Nordisk A/S, Novo Nordisk Park, 2760, Måløv, Denmark
| | - Trine Ryberg Clausen
- Global Drug Discovery, Novo Nordisk A/S, Novo Nordisk Park, 2760, Måløv, Denmark.
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Ludvigsen TP, Pedersen SF, Vegge A, Ripa RS, Johannesen HH, Hansen AE, Löfgren J, Schumacher-Petersen C, Kirk RK, Pedersen HD, Christoffersen BØ, Ørbæk M, Forman JL, Klausen TL, Olsen LH, Kjaer A. 18F-FDG PET/MR-imaging in a Göttingen Minipig model of atherosclerosis: Correlations with histology and quantitative gene expression. Atherosclerosis 2019; 285:55-63. [PMID: 31004968 DOI: 10.1016/j.atherosclerosis.2019.04.209] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [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] [Received: 10/29/2018] [Revised: 04/01/2019] [Accepted: 04/04/2019] [Indexed: 12/11/2022]
Abstract
BACKGROUND AND AIMS The advantage of combining molecular and morphological imaging, e.g. positron emission tomography and magnetic resonance imaging (PET/MRI), is reflected in the increased use of these modalities as surrogate end-points in clinical trials. This study aimed at evaluating plaque inflammation using 18F-fluorodeoxyglucose (18F-FDG)-PET/MRI, and gene expression in a minipig model of atherosclerosis. METHODS Göttingen Minipigs were fed for 60 weeks with fat/fructose/cholesterol-rich diet (FFC), chow (Control) or FFC-diet changed to chow midway (diet normalization group; DNO). In all groups, 18F-FDG-PET/MRI of the abdominal aorta was assessed midway and at study-end. The aorta was analyzed using histology and gene expression. RESULTS At study-end, FFC had significantly higher FDG-uptake compared to Control (target-to-background maximal uptake, TBRMax (95% confidence interval) CITBRMax: 0.092; 7.32) and DNO showed significantly decreased uptake compared to FFC (CITBRMax: -5.94;-0.07). No difference was observed between DNO and Control (CITBRMax: -2.71; 4.11). FFC displayed increased atherosclerosis and gene expression of inflammatory markers, including vascular cell adhesion molecule 1 (VCAM-1), cluster of differentiation 68 (CD68), matrix metalloproteinase 9 (MMP9), cathepsin K (CTSK) and secreted phosphoprotein 1 (SPP1) compared to Control and DNO (all, p < 0.05). FDG-uptake correlated with gene expression of inflammatory markers, including CD68, ρs = 0.58; MMP9, ρs = 0.46; SPP1, ρs = 0.44 and CTSK, ρs = 0.49; (p ≤ 0.01 for all). CONCLUSIONS In a model of atherosclerosis, 18F-FDG-PET/MRI technology allows for detection of inflammation in atherosclerotic plaques, consistent with increased inflammatory gene expression. Our findings corroborate clinical data and are important in pre-clinical drug development targeting plaque inflammation.
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Affiliation(s)
- Trine P Ludvigsen
- Global Drug Discovery, Novo Nordisk Park, Novo Nordisk A/S, DK-2760, Måløv, Denmark
| | - Sune F Pedersen
- Department of Clinical Physiology, Nuclear Medicine & PET and Cluster for Molecular Imaging, Dept. of Biomedical Sciences, Rigshospitalet and University of Copenhagen, Blegdamsvej 9, DK-2100, Copenhagen, Denmark
| | - Andreas Vegge
- Global Drug Discovery, Novo Nordisk Park, Novo Nordisk A/S, DK-2760, Måløv, Denmark
| | - Rasmus S Ripa
- Department of Clinical Physiology, Nuclear Medicine & PET and Cluster for Molecular Imaging, Dept. of Biomedical Sciences, Rigshospitalet and University of Copenhagen, Blegdamsvej 9, DK-2100, Copenhagen, Denmark
| | - Helle H Johannesen
- Department of Clinical Physiology, Nuclear Medicine & PET and Cluster for Molecular Imaging, Dept. of Biomedical Sciences, Rigshospitalet and University of Copenhagen, Blegdamsvej 9, DK-2100, Copenhagen, Denmark
| | - Adam E Hansen
- Department of Clinical Physiology, Nuclear Medicine & PET and Cluster for Molecular Imaging, Dept. of Biomedical Sciences, Rigshospitalet and University of Copenhagen, Blegdamsvej 9, DK-2100, Copenhagen, Denmark
| | - Johan Löfgren
- Department of Clinical Physiology, Nuclear Medicine & PET and Cluster for Molecular Imaging, Dept. of Biomedical Sciences, Rigshospitalet and University of Copenhagen, Blegdamsvej 9, DK-2100, Copenhagen, Denmark
| | - Camilla Schumacher-Petersen
- Department of Veterinary and Animal Sciences, University of Copenhagen, Ridebanevej 9, DK-1870, Frederiksberg, Denmark
| | - Rikke K Kirk
- Global Drug Discovery, Novo Nordisk Park, Novo Nordisk A/S, DK-2760, Måløv, Denmark
| | - Henrik D Pedersen
- Department of Veterinary and Animal Sciences, University of Copenhagen, Ridebanevej 9, DK-1870, Frederiksberg, Denmark; Ellegaard Göttingen Minipigs A/S, Sorø Landevej 302, DK-4261, Dalmose, Denmark
| | | | - Mathilde Ørbæk
- Department of Clinical Physiology, Nuclear Medicine & PET and Cluster for Molecular Imaging, Dept. of Biomedical Sciences, Rigshospitalet and University of Copenhagen, Blegdamsvej 9, DK-2100, Copenhagen, Denmark
| | - Julie L Forman
- Section of Biostatistics, Department of Public Health, University of Copenhagen, Øster Farimagsgade 5, DK-1014, Copenhagen, Denmark
| | - Thomas L Klausen
- Department of Clinical Physiology, Nuclear Medicine & PET and Cluster for Molecular Imaging, Dept. of Biomedical Sciences, Rigshospitalet and University of Copenhagen, Blegdamsvej 9, DK-2100, Copenhagen, Denmark
| | - Lisbeth H Olsen
- Department of Veterinary and Animal Sciences, University of Copenhagen, Ridebanevej 9, DK-1870, Frederiksberg, Denmark
| | - Andreas Kjaer
- Department of Clinical Physiology, Nuclear Medicine & PET and Cluster for Molecular Imaging, Dept. of Biomedical Sciences, Rigshospitalet and University of Copenhagen, Blegdamsvej 9, DK-2100, Copenhagen, Denmark.
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9
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Christoffersen BØ, Jensen SJ, Ludvigsen TP, Nilsson SK, Grossi AB, Heegaard PMH. Age- and Sex-Associated Effects on Acute-Phase Proteins in Göttingen Minipigs. Comp Med 2015; 65:333-341. [PMID: 26310463 PMCID: PMC4549679] [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: 02/06/2015] [Revised: 03/27/2015] [Accepted: 04/16/2015] [Indexed: 06/04/2023]
Abstract
Göttingen minipigs are a useful model for diseases having an inflammatory component, and the associated use of acute-phase proteins (APP) as biomarkers of inflammation warrants establishment of their reference ranges. The objective of this study was to establish reference values for selected APP in Göttingen minipigs and to investigate the effects of age, sex, and various stimuli on these ranges. Serum concentrations of C-reactive protein (CRP), serum amyloid A (SAA), haptoglobin, pig major acute-phase protein (PMAP), albumin, and porcine α-1 acid glycoprotein (PAGP) were evaluated in 4 age groups (6, 16, 24 and 40-48 wk) of male and female Göttingen minipigs. In addition, minipigs were tested under 2 housing conditions, after acute LPS challenge, and after diet-induced obesity with and without mild diabetes. Changing the pigs to a new environment induced significant increases in CRP, PMAP, haptoglobin and PAGP and a decrease in albumin. An acute LPS stimulus increased CRP, PMAP, haptoglobin, and SAA; PAGP was unchanged and albumin decreased. Obese pigs with and without diabetes showed increases in CRP and PAGP, albumin decreased, and haptoglobin and SAA were unchanged. PMAP was increased only in obese pigs without diabetes. In conclusion, reference values for CRP, PMAP, haptoglobin, SAA, PAGP and albumin were established for male and female Göttingen minipigs of different ages. These APP were influenced by age and sex, underlining the importance of considering these factors when designing and interpreting studies including aspects of inflammation. In addition, an APP response was verified after both acute and chronic stimuli.
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Affiliation(s)
| | - Søren J Jensen
- Department of Veterinary Disease Biology, University of Copenhagen, Frederiksberg, Denmark
| | - Trine P Ludvigsen
- Global Research, Novo Nordisk A/S, Copenhagen, Denmark, Department of Veterinary Disease Biology, University of Copenhagen, Frederiksberg, Denmark
| | - Sara K Nilsson
- Department of Veterinary Disease Biology, University of Copenhagen, Frederiksberg, Denmark, Current position is at Växa Sverige, Flen, Sweden
| | | | - Peter M H Heegaard
- Innate Immunology Group, National Veterinary Institute, Technical University of Denmark, Lyngby, 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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11
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Pedersen SF, Ludvigsen TP, Johannesen HH, Löfgren J, Ripa RS, Hansen AE, Ettrup AJ, Christoffersen BØ, Pedersen HD, Olsen LH, Højgaard L, Kjær A. Feasibility of simultaneous PET/MR in diet-induced atherosclerotic minipig: a pilot study for translational imaging. Am J Nucl Med Mol Imaging 2014; 4:448-458. [PMID: 25143863 PMCID: PMC4138139] [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] [Subscribe] [Scholar Register] [Received: 05/18/2014] [Accepted: 05/22/2014] [Indexed: 06/03/2023]
Abstract
Novel hybrid 18-fluoro-deoxy-D-glucose ((18)F-FDG) based positron emission tomography (PET) and magnetic resonance imaging (MRI) has shown promise for characterization of atherosclerotic plaques clinically. The purpose of this study was to evaluate the method in a pre-clinical model of diet-induced atherosclerosis, based on the Göttingen minipig. Using (18)F-FDG PET/MRI the goal was to develop and create a new imaging method in an in vivo animal model for translational studies of atherosclerosis. We used a strategy of multisequence MRI for optimal anatomical imaging of the abdominal aortas of the pigs (n=4): T1-weighted turbo spin-echo (T1-TSE), T2-weighted turbo spin-echo (T2-TSE) and proton density imaging with and without fat saturation. (18)F-FDG PET emission data were collected from a single bed position of the abdominal aorta in 3D mode for either 10 (n=4) or 10 and 20 minutes (n=2) to measure glycolysis as given by standardized uptake values (SUV). Ex vivo en face evaluation of aortas from an atherosclerotic animal illustrated plaque distribution macroscopically, compared to a lean control animal. Although T2-TSE weighted imaging was most consistent, no one MRI sequence was preferable and superior to another for visualization and identification of the abdominal aorta. We found poor correlation between SUVs obtained from 10 and 20 minutes of reconstructed PET emission data. This can most likely be ascribed to intestinal movement. In conclusion multisequence MRI is recommended for optimal imaging of the abdominal aorta using MRI. Furthermore we found that 10 minutes of PET emission data seems adequate. This is the first study to demonstrate that the method of (18)F-FDG PET/MRI is feasible in minipig models of atherosclerosis, and therefore relevant in larger prospective studies. Perspectives of the method include correlation to e.g. aortic immunohistochemistry findings and a range of genomic and proteomic analyses.
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Affiliation(s)
- Sune F Pedersen
- Cluster for Molecular Imaging, University of Copenhagen; Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet, University of Copenhagen Copenhagen, Denmark
| | - Trine P Ludvigsen
- Department of Veterinary Disease Biology, University of Copenhagen Frederiksberg, Denmark
| | - Helle H Johannesen
- Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet, University of Copenhagen Copenhagen, Denmark
| | - Johan Löfgren
- Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet, University of Copenhagen Copenhagen, Denmark
| | - Rasmus S Ripa
- Cluster for Molecular Imaging, University of Copenhagen; Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet, University of Copenhagen Copenhagen, Denmark
| | - Adam E Hansen
- Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet, University of Copenhagen Copenhagen, Denmark
| | - Anders J Ettrup
- Neurobiology Research Unit, Rigshospitalet, University of Copenhagen Copenhagen, Denmark
| | | | | | - Lisbeth H Olsen
- Department of Veterinary Disease Biology, University of Copenhagen Frederiksberg, Denmark
| | - Liselotte Højgaard
- Cluster for Molecular Imaging, University of Copenhagen; Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet, University of Copenhagen Copenhagen, Denmark
| | - Andreas Kjær
- Cluster for Molecular Imaging, University of Copenhagen; Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet, University of Copenhagen Copenhagen, Denmark
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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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13
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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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14
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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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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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