Torben Larsen

Torben Larsen


Research Focus & Metrics

Academic Career Length

39Years (1988-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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2 January 2013 in Science Translational Medicine
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RARozh Al-Mashhadi
Rozh Al-Mashhadi
CSCharlotte B. Sørensen
Charlotte B. Sørensen
PKPeter M. Kragh
Peter M. Kragh
CCChristina Christoffersen
Christina Christoffersen
MMMartin B. Mortensen
Martin B. Mortensen
JBJacob F. Bentzon
Jacob F. Bentzon
Lack of animal models with human-like size and pathology hampers translational research in atherosclerosis. Mouse models are missing central features of human atherosclerosis and are too small for intravascular procedures and imaging. Modeling the disease in minipigs may overcome these limitations, but it has proven difficult to induce rapid atherosclerosis in normal pigs by high-fat feeding alone, and genetically modified models similar to those created in mice are not available. D374Y gain-of-function mutations in the proprotein convertase subtilisin/kexin type 9 (PCSK9) gene cause severe autosomal dominant hypercholesterolemia and accelerates atherosclerosis in humans. Using Sleeping Beauty DNA transposition and cloning by somatic cell nuclear transfer, we created Yucatan minipigs with liver-specific expression of human D374Y-PCSK9. D374Y-PCSK9 transgenic pigs displayed reduced hepatic low-density lipoprotein (LDL) receptor levels, impaired LDL clearance, severe hypercholesterolemia, and spontaneous development of progressive atherosclerotic lesions that could be visualized by noninvasive imaging. This model should prove useful for several types of translational research in atherosclerosis.

1 May 2012 in Journal of Dairy Science
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Journal Article
Open access
VBV. Bjerre-Harpøth
V. Bjerre-Harpøth
NFN.C. Friggens
N.C. Friggens
VTV.M. Thorup
V.M. Thorup
TLTorben Larsen
Torben Larsen
BDB.M. Damgaard
B.M. Damgaard
KMK.M. Moyes
K.M. Moyes
Physiological imbalance (PI) is a situation in which physiological parameters deviate from the normal, and cows consequently have an increased risk of developing production diseases and reduced production or reproduction. Our objectives were to (1) determine the effect of stage of lactation and milk yield on metabolic and production responses of cows during a nutrient restriction period to experimentally increase PI; (2) identify major metabolites that relate to degree of PI; and (3) identify potential biomarkers in milk for on-farm detection of PI throughout lactation. Forty-seven Holstein cows in early [n=14; 49±22 d in milk (DIM); parity=1.6±0.5], mid (n=15; 159±39 DIM; parity=1.5±0.5), and late (n=18; 273±3 DIM; parity=1.3±0.5) lactation were used. Prior to restriction, all cows were fed the same total mixed ration ad libitum. All cows were then nutrient restricted for 4 d by supplementing the ration with 60% wheat straw to induce PI. After restriction, cows returned to full feed. Daily milk yield was recorded and composite milk samples were analyzed for fat, protein, lactose, citrate, somatic cells, uric acid, alkaline phosphatase, β-hydroxybutyrate (BHBA), and milk urea nitrogen. Blood was collected daily and analyzed for metabolites: nonesterified fatty acids (NEFA), BHBA, glucose, plasma urea nitrogen, and insulin. The revised quantitative insulin sensitivity check index (RQUICKI) was calculated for each cow. Liver biopsies collected before and during restriction were analyzed for triglycerides, glycogen, phospholipids, glucose, and total lipid content. A generalized linear mixed model was used to determine the effect of stage of lactation on responses during restriction. Regression analyses were used to examine the effect of pre-restriction levels on changes during restriction. Similar decreases in milk yield among groups indicate that the capacity of individual responses is dependent on milk yield but the coping strategies used are dependent on stage of lactation. Milk yield was a better predictor of feed intake than DIM. Plasma glucose decreased for all cows, and cows in early lactation had increased plasma BHBA, whereas cows in later lactation had increased NEFA during restriction. Milk citrate had the greatest increase (58%) during restriction for all cows. Results reported here identified metabolites (i.e., glucose, NEFA, BHBA, cholesterol) as predictors of PI and identified milk citrate as a promising biomarker for PI on farm.

1 February 2000 in British Journal of Nutrition
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TLTorben Larsen
Torben Larsen
STShakuntala Haraksingh Thilsted
Shakuntala Haraksingh Thilsted
KKKatja Kongsbak
Katja Kongsbak
MHMarianne Hansen
Marianne Hansen
The present rat balance study investigated Ca availability from the whole indigenous small fish species, mola (Amblypharyngodon mola) from Bangladesh and from skimmed milk. Four groups of six young male rats each were fedad libitumwith diets containing either small fish or milk, at 100 or 160 g crude protein/kg diet dry matter. The study was conducted for 28 d and faeces and urine samples were collected in two balance periods: days 8–14 and 22–28. The Ca and N contents of the diets, faeces and urine were analysed. Ca intake, fractional Ca absorption and Ca retention in relation to N retention were measured. Digestibility and protein utilization of the experimental diets, weight gain of the rats, femur bone weight and mineral composition as well as bone alkaline phosphatase activity were also determined. It was concluded from the values of these variables that Ca from small fish with bones was available and appeared to be a useful Ca source in rats, though perhaps not as available as Ca from milk. This study suggests that small fish with bones may be an important source of Ca in human diets. Promotion of the production and consumption of small fish in population groups with low intakes of milk and milk products should therefore be encouraged.

1 January 2006 in International Journal of Food Sciences and Nutrition
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Journal Article
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DCDirk L. Christensen
Dirk L. Christensen
FOFrancis O. Orech
Francis O. Orech
MMMichael N. Mungai
Michael N. Mungai
TLTorben Larsen
Torben Larsen
HFHenrik Friis
Henrik Friis
JAJens Aagaard-Hansen
Jens Aagaard-Hansen
Primary objective To determine the iron, zinc, and calcium content in different insects commonly eaten among the Luo of Kenya. Research design A cross-sectional design was chosen for the study in order to determine the insects eaten and their mineral content during a specific season. Methods and procedures Five different insect species were identified and collected with the help of local informants in the Nyang'oma sublocation of the Bondo district in western Kenya, and were analysed for iron, zinc and calcium contents. Main outcomes and results The iron content ranged from 18 to 1562 mg/100 g dry matter, the zinc content from 8 to 25 mg/100 g, and the calcium content from 33 to 341 mg/100 g in five different insects, onyoso mammon (ant), oyala (termite), ogawo (termite), agaor (termite), onjiri mammon (cricket). Conclusions Insect eating could prove to be a valuable measure to combat, especially, iron and zinc deficiency in developing countries.

11 September 2017 in Nature Communications
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Journal Article
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CGCamilla Gustafsen
Camilla Gustafsen
DODitte Olsen
Ditte Olsen
JVJoachim Vilstrup
Joachim Vilstrup
SLSigne Lund
Signe Lund
ARAnika Reinhardt
Anika Reinhardt
SGSimon Glerup
Simon Glerup
Coronary artery disease is the main cause of death worldwide and accelerated by increased plasma levels of cholesterol-rich low-density lipoprotein particles (LDL). Circulating PCSK9 contributes to coronary artery disease by inducing lysosomal degradation of the LDL receptor (LDLR) in the liver and thereby reducing LDL clearance. Here, we show that liver heparan sulfate proteoglycans are PCSK9 receptors and essential for PCSK9-induced LDLR degradation. The heparan sulfate-binding site is located in the PCSK9 prodomain and formed by surface-exposed basic residues interacting with trisulfated heparan sulfate disaccharide repeats. Accordingly, heparan sulfate mimetics and monoclonal antibodies directed against the heparan sulfate-binding site are potent PCSK9 inhibitors. We propose that heparan sulfate proteoglycans lining the hepatocyte surface capture PCSK9 and facilitates subsequent PCSK9:LDLR complex formation. Our findings provide new insights into LDL biology and show that targeting PCSK9 using heparan sulfate mimetics is a potential therapeutic strategy in coronary artery disease.

1 March 1993 in The Journal of Nutrition
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Journal Article
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ASAnn-Sofie Sandberg
Ann-Sofie Sandberg
TLTorben Larsen
Torben Larsen
BSBrittmarie Sandström
Brittmarie Sandström
The degradation of phytate (inositol hexaphosphate) in rapeseed meal diet not containing phytase activity was studied in 15 growing ileum-fistulated pigs. Stomach and small intestinal degradation and total gastrointestinal degradation were compared. The effect of addition of calcium carbonate to the rapeseed meal diet at two levels (9.2 and 18.5 g/kg diet) was investigated. A commercial barley-wheat-soybean diet with intrinsic phytase activity was used as reference. Phytate and its hydrolysis products in diets, ileal digesta and feces were determined by HPLC ion-pair chromatography. Hydrolysis of phytate in the stomach and small intestine was 35–45% in pigs fed the rapeseed meal diet independent of calcium addition, and 65% in pigs fed the reference diet. Total gastrointestinal degradation of phytate in pigs fed the rapeseed diet was 97, 77 and 42% (P < 0.001) when calcium intakes were 4.5, 9.9 and 15 g/d, respectively; total gastrointestinal degradation was 72% in pigs fed the reference diet. The intestinal phytate degradation pattern, when rapeseed diet was fed, indicated the activity of an unspecific phosphatase, whereas that of the reference diet indicated intrinsic dietary phytase activity. We conclude that dietary supplementation of calcium carbonate decreases the phytate degradation in the colon of pigs, but not in the stomach and small intestine.