Staff Publications

Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

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B Vitamins Can Reduce Body Weight Gain by Increasing Metabolism-related Enzyme Activities in Rats Fed on a High-Fat Diet
Zheng, Ying ; Ma, A. ; Zheng, Ming C. ; Wang, Qiuzhen ; Liang, Hui ; Han, Xiuxia ; Schouten, Evert G. - \ 2018
Current Medical Science 38 (2018)1. - ISSN 2096-5230 - p. 174 - 183.
B vitamins - body weight gain - enzyme activities - obesity - rats

B vitamins are enzyme cofactors that play an important role in energy metabolism. The aim of this study was to elucidate whether B vitamin administration can reduce body weight (BW) gain by improving energy metabolism-related enzyme activities in rats fed on a highfat diet. Fifty rats were randomly assigned to one of the following five groups: control group (C), including rats fed on standard rat chow; four treatment groups (HO, HI, H2, and H3), in which rats were fed on a high-fat diet. Rats in the HI group were treated daily with 100 mg/kg BW thiamine (VB1), 100 mg/kg BW riboflavin (VB2), and 250 mg/kg BW niacin (VPP); rats in the H2 group were treated daily with 100 mg/kg BW pyridoxine (VB6), 100 mg/kg BW cobalamin (VB12), and 5 mg/kg BW folate (FA); and rats in the H3 group were treated daily with all of the B vitamins administered to the HI and H2 groups. After 12 weeks, the BW gains from the initial value were 154.5±58.4 g and 159.1±53.0 g in the HI and C groups, respectively, which were significantly less than the changes in the HO group (285.2±14.8 g, P<0.05). In the HO group, the plasma total cholesterol (CHO) and triglyceride (TG) levels were 1.59±0.30 mmol/L and 1,55±0.40 mmol/L, respectively, which were significantly greater than those in the HI group (1.19±0.18 mmol/L and 0.76±0.34 mmol/L, respectively, P<0.05). The activities of transketolase (TK), glutathione reductase, and Na+/K+ adenosine triphosphatase were significantly increased in the B vitamin-treated groups and were significantly greater than those in the HO group (P<0.05). Furthermore, the glucose-6-phosphate dehydrogenase, pyruvic acid kinase, and succinate dehydrogenase activities also were increased after treatment with B vitamins. Supplementation with B vitamins could effectively reduce BW gain and plasma levels of lipids by improving energy metabolism-related enzyme activities in rats, thus possibly providing potential benefits to humans.

Influence of pectin supplementation on feed fermentation characteristics in rats and pigs
Tian, L. - \ 2016
Wageningen University. Promotor(en): Harry Gruppen; Henk Schols. - Wageningen : Wageningen University - ISBN 9789462577282 - 142 p.
pigs - rats - pectins - feed supplements - dietary fibres - digestion - digestive tract - carbohydrates - microbial flora - nutrition physiology - animal nutrition - food chemistry - varkens - ratten - pectinen - voedersupplementen - voedingsvezels - spijsvertering - spijsverteringskanaal - koolhydraten - microbiële flora - voedingsfysiologie - diervoeding - voedselchemie

The physiological effects of dietary fiber (DFs) depend on several factors including structural features of the DFs, composition and activity of colonic microbiota, and products formed during fermentation. In this thesis, the influence of pectin supplementation to feed fermentation characteristics in rats and pigs was studied. The non-starch polysaccharides (NSP) present in the selected feed ingredient oats were characterized. Distinct populations of arabinoxylans (AXs) were observed in oats, compared to those reported for other cereals like wheat and barley. The fate of cereal AXs and soybean pectin during fermentation and the consequent effects on appetite regulation and fat accumulation were studied in rats as a model. Oat AXs were fermented less rapidly than wheat AXs in the caecum of rats. Soy pectin was fermented more early and efficiently than cereal AXs. A significant inverse correlation between rat retroperitoneal fat-pad weight and concentration and relative SCFA proportion of butyrate was observed. In a following in vivo rat experiment, commercial soy pectin together with three other soluble pectins originating from citrus and sugar beet and differing in their methyl esterification were individually supplemented to the diets. Their effects on the utilization of the different DFs present in the feed and the consequent effect on the microbial community in the colon of rats was studied. All pectins were fermented rapidly and consequently shifted fermentation of other consumed DFs (e.g. cereal AXs) to more distal part of colon, although low-methyl esterified pectin was more efficiently fermented by the microbiota than high-methyl esterified pectin. Results suggested that pectins can confer beneficial health effects through modulation of the gut microbiota. In a last in vivo experiment, citrus pectins together with a hydrothermal treated soybean meal were supplemented to pig diets to study their effect on the digestion and fermentation of carbohydrates in both the small and large intestine. Pectins, and more particularly low-methyl esterified pectin, decreased the ileal digestibility of digestible starch resulting in more starch to be fermentated in the proximal colon of pigs. Consequently, also the fermentation patterns of DFs and the microbiota composition was affected. All pectins tested shaped the colonic microbiota from a Lactobacillus-dominated microbiota to a Prevotella-dominated community, with potential health-promoting effects.

Quercetin tests negative for genotoxicity in transcriptome analyses of liver and small intestine of mice
Hil, E.F. van den; Schothorst, E.M. van; Stelt, I. van der; Keijer, J. ; Rietjens, I. - \ 2015
Food and Chemical Toxicology 81 (2015). - ISSN 0278-6915 - p. 34 - 39.
in-vivo - reverse mutation - bone-marrow - dna-damage - flavonoids - rats - cells - carcinogenicity - mutagenicity - polyphenols
Given the positive results of quercetin in in vitro genotoxicity studies, the in vivo genotoxic properties of this important dietary flavonoid warrant testing, especially considering possible high intake via widely available food supplements. Here, this was done by transcriptome analyses of the most relevant tissues, liver and small intestine, of quercetin supplemented mice. Quercetin (0.33%) supplemented to a high-fat diet was administered to mice during 12 weeks. Serum alanine aminotransferase and aspartate aminotransferase levels revealed no indications for hepatotoxicity. Microarray pathway analysis of liver and small intestine showed no regulation of genotoxicity related pathways. Analysis of DNA damage related genes also did not point at genotoxicity. Furthermore, a published classifier set of transcripts for identifying genotoxic compounds did not indicate genotoxicity. Only two transcripts of the classifier set were regulated, but in the opposite direction compared with the genotoxic compounds 2-acetylaminofluorene (2-AAF) and aflatoxin B1 (AFB1). Based on the weight of evidence of three different types of analysis, we conclude that supplementation with quercetin at ~350¿mg/kg bw/day for 12 weeks in mice showed no up-regulation of genotoxicity related pathways in liver and small intestine.
Cholecystokinin regulates satiation idependently of the abdominal vagal nerve in a pig model of total subdiaphragmatic vagotomy
Ripken, D. ; Wielen, N. van der; Meulen, J. van der; Schuurman, T. ; Witkamp, R.F. ; Hendriks, H.F.J. ; Koopmans, S.J. - \ 2015
Physiology and Behavior 139 (2015)2015. - ISSN 0031-9384 - p. 167 - 176.
glucagon-like peptide-1 - food-intake - paracetamol absorption - physiological-role - appetite control - exendin 9-39 - rats - glp-1 - antagonist - afferents
The vagal nerve and gut hormones CCK and GLP-1 play important roles in the control of food intake. However, it is not clear to what extent CCK and GLP-1 increase satiation by stimulating receptors located on abdominal vagal nerve endings or via receptors located elsewhere. This study aimed to further explore the relative contribution of the abdominal vagal nerve in mediating the satiating effects of endogenous CCK and GLP-1. Total subdiaphragmatic vagotomy or sham operation was combined with administration of CCK1 and GLP-1 receptor antagonists devazepide and exendin (9–39) in 12 pigs, applying an unbalanced Latin Square within-subject design. Furthermore, effects of vagotomy on preprandial and postprandial acetaminophen absorption, glucose, insulin, GLP-1 and CCK plasma concentrations were investigated. Ad libitum liquid meal intake (mean ± SEM) was similar in sham and vagotomized pigs (4180 ± 435 and 3760 ± 810 g/meal). Intake increased by about 20% after blockade of CCK1 receptors, independently of the abdominal vagal nerve. Food intake did not increase after blockade of GLP-1 receptors. Blockade of CCK1 and GLP-1 receptors increased circulating CCK and GLP-1 concentrations in sham pigs only, suggesting the existence of a vagal reflex mechanism in the regulation of plasma CCK1 and GLP-1 concentrations. Vagotomy decreased acetaminophen absorption and changed glucose, insulin, CCK and GLP-1 concentrations indicating a delay in gastric emptying. Our data show that at liquid feeding, satiation is decreased effectively by pharmacological blockade of CCK1 receptors. We conclude that regulation of liquid meal intake appears to be primarily regulated by CCK1 receptors not located on abdominal vagal nerve endings.
Authentication of Geographical Origin and Crop System of Grape Juices by Phenolic Compounds and Antioxidant Activity Using Chemometrics
Granato, D. ; Koot, A.H. ; Schnitzler, E. ; Ruth, S.M. van - \ 2015
Journal of Food Science 80 (2015)3. - ISSN 0022-1147 - p. C584 - C593.
in-vitro - red wines - oxidative stress - fruit juices - rats - capacity - vivo - mechanism - profile
The main goal of this work was to propose an authentication model based on the phenolic composition and antioxidant and metal chelating capacities of purple grape juices produced in Brazil and Europe in order to assess their typicality. For this purpose, organic, conventional, and biodynamic grape juices produced in Brazil (n = 65) and in Europe (n = 31) were analyzed and different multivariate class-modeling and classification statistical techniques were employed to differentiate juices based on the geographical origin and crop system. Overall, Brazilian juices, regardless of the crop system adopted, presented higher contents of total phenolic compounds and flavonoids, total monomeric anthocyanins, proanthocyanidins, flavonols, flavanols, cyanidin-3-glucoside, delphinidin-3-glucoside, and malvidin-3,5-glucoside. No differences were observed for trans-resveratrol, malvidin-3-glucoside, and pelargonidin-3-glucoside between countries and among crop systems. A total of 91% of Brazilian and 97% of European juices were adroitly classified using partial least squares discriminant analysis when the producing region was considered (92% efficiency), in which the free-radical scavenging activity toward 2,2-diphenyl-1-picrylhydrazyl, content of total phenolic compounds, gallic acid, and malvidin-3-glucoside were the variables responsible for the classification. Intraregional models based on soft independent modeling of class analogy were able to differentiate organic from conventional Brazilian juices as well as conventional and organic/biodynamic European juices.
Successful validation of genomic biomarkers for human immunotoxicity in Jurkat T cells in vitro
Schmeits, P.C.J. ; Shao, J. ; Krieken, D.A. van der; Volger, O.L. ; Loveren, H. van; Peijnenburg, A.A.C.M. ; Hendriksen, P.J.M. - \ 2015
Journal of Applied Toxicology 35 (2015)7. - ISSN 0260-437X - p. 831 - 841.
polycyclic aromatic-hydrocarbons - brominated flame retardants - tetrabromobisphenol-a - balb/c mice - vitamin-c - chlorpyrifos - activation - exposure - rats - kinase
Previously, we identified 25 classifier genes that were able to assess immunotoxicity using human Jurkat T cells. The present study aimed to validate these classifiers. For that purpose, Jurkat cells were exposed for 6¿h to subcytotoxic doses of nine immunotoxicants, five non-immunotoxicants and four compounds for which human immunotoxicity has not yet been fully established. RNA was isolated and subjected to Fluidigm quantitative real time (qRT)–PCR analysis. The sensitivity, specificity and accuracy of the screening assay as based on the nine immunotoxicants and five non-immunotoxicants used in this study were 100%, 80% and 93%, respectively, which is better than the performance in our previous study. Only one compound was classified as false positive (benzo-e-pyrene). Of the four potential (non-)immunotoxicants, chlorantraniliprole and Hidrasec were classified immunotoxic and Sunset yellow and imidacloprid as non-immunotoxic. ToxPi analysis of the PCR data provided insight in the molecular pathways that were affected by the compounds. The immunotoxicants 2,3-dichloro-propanol and cypermethrin, although structurally different, affected protein metabolism and cholesterol biosynthesis and transport. In addition, four compounds, i.e.¿chlorpyrifos, aldicarb, benzo-e-pyrene and anti-CD3, affected genes in cholesterol metabolism and transport, protein metabolism and transcription regulation. qRT–PCR on eight additional genes coding for similar processes as defined in ToxPi analyzes, supported these results. In conclusion, the 25 immunotoxic classifiers performed very well in a screening with new non-immunotoxic and immunotoxic compounds. Therefore, the Jurkat screening assay has great promise to be applied within a tiered approach for animal free testing of human immunotoxicity.
Induced lung inflammation and dietary protein supply affect nitrogen retention and amino acid metabolism in growing pigs
Kampman-van de Hoek, E. ; Sakkas, P. ; Gerrits, W.J.J. ; Borne, J.J.G.C. van den; Peet-Schwering, C.M.C. van der; Jansman, A.J.M. - \ 2015
The British journal of nutrition 113 (2015)3. - ISSN 0007-1145 - p. 414 - 425.
immune-system activation - acute-phase proteins - body protein - tryptophan - plasma - growth - piglets - disease - sepsis - rats
It is hypothesised that during immune system activation, there is a competition for amino acids (AA) between body protein deposition and immune system functioning. The aim of the present study was to quantify the effect of immune system activation on N retention and AA metabolism in growing pigs, depending on dietary protein supply. A total of sixteen barrows received an adequate (Ad) or restricted (Res) amount of dietary protein, and were challenged at day 0 with intravenous complete Freund's adjuvant (CFA). At days - 5, 3 and 8, an irreversible loss rate (ILR) of eight AA was determined. CFA successfully activated the immune system, as indicated by a 2- to 4-fold increase in serum concentrations of acute-phase proteins (APP). Pre-challenge C-reactive protein concentrations were lower (P<0·05) and pre- and post-challenge albumin tended to be lower in Res-pigs. These findings indicate that a restricted protein supply can limit the acute-phase response. CFA increased urinary N losses (P= 0·04) and tended to reduce N retention in Ad-pigs, but not in Res-pigs (P= 0·07). The ILR for Val was lower (P= 0·05) at day 8 than at day 3 in the post-challenge period. The ILR of most AA, except for Trp, were strongly affected by dietary protein supply and positively correlated with N retention. The correlations between the ILR and APP indices were absent or negative, indicating that changes in AA utilisation for APP synthesis were either not substantial or more likely outweighed by a decrease in muscle protein synthesis during immune system activation in growing pigs.
Dietary Linoleic and a-Linolenic Acid Affect Anxiety-Related Responses and Exploratory Activity in Growing Pigs
Clouard, C.M. ; Gerrits, W.J.J. ; Kerkhof, I. van; Smink, W. ; Bolhuis, J.E. - \ 2015
The Journal of Nutrition 145 (2015)2. - ISSN 0022-3166 - p. 358 - 364.
polyunsaturated fatty-acids - docosahexaenoic acid - inflammatory processes - open-field - behavior - brain - rats - mice - deficiency - piglets
Background: Growing evidence suggests that the dietary ratio of linoleic acid (LA) to a-linolenic acid (ALA), the precursors of arachidonic acid (AA) and docosahexaenoic acid (DHA), respectively, may affect behavior in mammals. Objective: This study aimed at evaluating the impact of dietary LA and ALA intake on behaviors of growing pigs, a pertinent model for human nutrition. Methods: At 7 wk of age, 32 pigs were allocated to 4 dietary treatments varying in daily intake of LA (1.3 and 2.6 g · kg body weight-0.75 · d-1 for low- and high-LA groups, respectively) and ALA (0.15 and 1.5 g · kg body weight-0.75 · d-1 for low- and high-ALA groups, respectively) for 4 wk. Between days 12 and 18, general behavior in the home pen was observed and pigs were subjected to an open field and novel object test. At 11 wk of age, brain fatty acid composition was analyzed. Results: Compared with high LA intake, low LA intake increased the time spent on exploration, particularly nosing in the home pen (P <0.05) and the open field (P <0.05), and tended to reduce the time spent lying with eyes open in the home pen (P = 0.09). Time spent lying with eyes open also tended to be affected by LA × ALA interaction (P = 0.08). A high-LA/high-ALA intake (ratio of 2; P <0.05) and a low-LA/high-ALA intake (ratio of 1; P = 0.06) decreased the latency to approach the novel object compared with a low-LA/low-ALA intake (ratio of 9). DHA in the frontal cortex was positively correlated with exploratory behaviors in the home pen (rs = 0.56, P <0.01), whereas AA was negatively correlated with time spent lying with eyes closed (rs = –0.48, P <0.01). Conclusions: Low LA intake and a low dietary LA:ALA ratio increased exploration and decreased anxiety-related behaviors in pigs. It is suggested that changes in brain DHA and AA induced by dietary LA and ALA intake mediate these behavioral changes.
Circulating angiopoietin-like 4 links proteinuria with hypertriglyceridemia in nephrotic syndrome
Clement, L.C. ; Mace, C. ; Avila-Casado, C. ; Joles, J.A. ; Kersten, A.H. ; Chugh, S.S. - \ 2014
Nature Medicine 20 (2014)1. - ISSN 1078-8956 - p. 37 - 46.
lipoprotein-lipase - fatty-acids - gene-expression - adipose-tissue - angptl4 - disease - serum - rats - mice - glomeruli
The molecular link between proteinuria and hyperlipidemia in nephrotic syndrome is not known. We show in the present study that plasma angiopoietin-like 4 (Angptl4) links proteinuria with hypertriglyceridemia through two negative feedback loops. In previous studies in a rat model that mimics human minimal change disease, we observed localized secretion by podocytes of hyposialylated Angptl4, a pro-proteinuric form of the protein. But in this study we noted high serum levels of Angptl4 (presumably normosialylated based on a neutral isoelectric point) in other glomerular diseases as well. Circulating Angptl4 was secreted by extrarenal organs in response to an elevated plasma ratio of free fatty acids (FFAs) to albumin when proteinuria reached nephrotic range. In a systemic feedback loop, these circulating pools of Angptl4 reduced proteinuria by interacting with glomerular endothelial alpha(v)beta(5) integrin. Blocking the Angptl4-beta(5) integrin interaction or global knockout of Angptl4 or beta(5) integrin delayed recovery from peak proteinuria in animal models. But at the same time, in a local feedback loop, the elevated extrarenal pools of Angptl4 reduced tissue FFA uptake in skeletal muscle, heart and adipose tissue, subsequently resulting in hypertriglyceridemia, by inhibiting lipoprotein lipase (LPL)-mediated hydrolysis of plasma triglycerides to FFAs. Injecting recombinant human ANGPTL4 modified at a key LPL interacting site into nephrotic Buffalo Mna and Zucker Diabetic Fatty rats reduced proteinuria through the systemic loop but, by bypassing the local loop, without increasing plasma triglyceride levels. These data show that increases in circulating Angptl4 in response to nephrotic-range proteinuria reduces the degree of this pathology, but at the cost of inducing hypertriglyceridemia, while also suggesting a possible therapy to treat these linked pathologies.
De Bruine rat in en om stadswoningen. Voorkomen is beter dan bestrijden
Adrichem, M.H.C. van; Buijs, J.A. ; Goedhart, P.W. ; Verboom-Vasiljev, J. - \ 2014
WT - Afvalwater 14 (2014)4. - ISSN 1879-8780 - p. 408 - 412.
ongediertebestrijding - ratten - plagenbehandeling - oorzakelijkheid - biotopen - riolering - inspectie - stedelijke gebieden - amsterdam - vermin control - rats - pest management - causality - biotopes - sewerage - inspection - urban areas
Omdat de mens overlast ervaart van ratten, worden ze al tientallen jaren bestreden met rodenticiden, waardoor de overlevingskans van resistente ratten is vergroot. De afdeling Dierplaagbeheersing van de GGD in Amsterdam probeert tegenwoordig de oorzaken te vinden waardoor overlast is ontstaan.
Differential regulation of pancreatic digestive enzymes during chronic high-fat diet-induced obesity in C57BL/6J mice
Birk, R.Z. ; Rubio-Aliaga, I. ; Boekschoten, M.V. ; Danino, H. ; Müller, M.R. ; Daniel, H. - \ 2014
The British journal of nutrition 112 (2014)2. - ISSN 0007-1145 - p. 154 - 161.
lipase messenger-rna - 2 related proteins - exocrine pancreas - cholesterol absorption - insulin-resistance - rats - adaptation - cholecystokinin - expression - colipase
Exocrine pancreatic digestive enzymes are essential for the digestion of dietary components and are regulated by them. Chronic excess dietary high fat (HF) consumption is a contributing factor of diet-induced obesity (DIO) and associated chronic diseases and requires adaptation by the pancreas. The aim of the present study was to investigate the effects of chronic HF diet feeding on exocrine pancreatic digestive enzyme transcript levels in DIO C57BL/6J mice. C57BL/6J mice were fed diets containing either 10 or 45 % energy (E%) derived from fat for 12 weeks (n 10 mice per diet group). Pancreatic tissue and blood samples were collected at 0, 4 and 12 weeks. The expression of a panel of exocrine pancreatic digestive enzymes was analysed using quantitative RT-PCR and Western blot analysis. The HF (45 E%) diet-fed C57BL/6J mice developed obesity, hyperleptinaemia, hyperglycaemia and hyperinsulinaemia. The transcript levels of pancreatic lipase (PL), pancreatic lipase-related protein 2 (PLRP2) and pancreatic phospholipase A2 (PLA2) were initially elevated; however, they were down-regulated to basal control levels at week 12. The transcript levels of colipase were significantly affected by diet and time. The protein levels of PL and PLRP2 responded to HF diet feeding. The transcript levels of amylase and proteases were not significantly affected by diet and time. The transcript levels of specific lipases in hyperinsulinaemic, hyperleptinaemic and hyperglycaemic DIO C57BL/6J mice are down-regulated. However, these mice compensate for this by the post-transcriptional regulation of the levels of proteins that respond to dietary fat. This suggests a complex regulatory mechanism involved in the modulation of fat digestion.
Optimizing soaking and germination conditions to improve gamma-aminobutyric acid content in japonica and indica germinated brown rice
Zhang, Q. ; Xiang, J. ; Zhang, L. ; Zhu, X. ; Evers, J.B. ; Werf, W. van der; Duan, L. - \ 2014
Journal of Functional Foods 10 (2014). - ISSN 1756-4646 - p. 283 - 291.
glutamate-decarboxylase - protease activities - blood-pressure - water soaking - giant-embryo - gaba - accumulation - metabolism - beans - rats
Germinated brown rice is a well-known functional food due to its high content of gamma-aminobutyric acid (GABA). This study was designed to test the difference of producing GABA in two domesticated rice genotypes (indica and japonica rice), and the effects of adding exogenous glutamic acid or gibberellin, and processing conditions. Soaking at 30¿°C and germination at 35¿°C during 36¿h resulted in the highest GABA in distilled soaking water with pH¿7. The indica rice showed higher GABA levels than japonica rice. GABA was increased under acidic soaking conditions or by adding L-glutamic acid (L-Glu) at the optimal concentration of 1.0¿g¿L-1 and gibberellin A3 (GA3) at the optimal concentration of 0.25¿mg¿L-1. The lower accumulation of GABA in japonica rice could be remedied by adding exogenous L-Glu and GA3, and providing acidic soaking conditions. The results help to efficiently produce GABA enriched functional food.
Malabaricone C-containing mace extract inhibits safrole bioactivation and DNA adduct formation both in vitro and in vivo
Martati, E. ; Boonpawa, R. ; Berg, J.H.J. van den; Paini, A. ; Spenkelink, A. ; Punt, A. ; Vervoort, J.J.M. ; Bladeren, P.J. van; Rietjens, I. - \ 2014
Food and Chemical Toxicology 66 (2014). - ISSN 0278-6915 - p. 373 - 384.
hepatocarcinogen safrole - carcinogenic metabolite - oral-cancer - mouse-liver - estragole - rats - 1'-hydroxysafrole - mice - sulfotransferases - pentachlorophenol
Safrole, present in mace and its essential oils, causes liver tumors in rodents at high dose levels due to formation of a DNA reactive 1'-sulfooxysafrole. The present study identifies malabaricone C as a mace constituent able to inhibit safrole DNA adduct formation at the level of sulfotransferase mediated bioactivation. This inhibition was incorporated into physiologically based biokinetic rat and human models. Dosing safrole at 50 mg/kg body weight and malabaricone C-containing mace extract at a ratio reflecting the relative presence in mace, and assuming 100% or 1% uptake of malabaricone C-containing mace extract, the model predicted inhibition of 1'-sulfooxysafrole formation for rats and humans by 90% and 100% or 61% and 91%, respectively. To validate the model, mace extract and safrole were co-administered orally to Sprague-Dawley rats. LC-ECI-MS/MS based quantification of DNA adduct levels revealed a significant (p <0.01) 55% reduction of safrole DNA adduct formation by malabaricone C-containing mace extract in the liver of rats exposed to safrole. The data obtained were used to perform a refined risk assessment of safrole. Overall, the results suggest a lower tumor incidence when safrole would be tested within a relevant food matrix containing sulfotransferase inhibitors compared to dosing pure safrole.
Increasing protein intake modulates lipid metabolism in healthy young men and women consuming a high-fat hypercaloric diet 1-3
Rietman, A. ; Schwarz, J. ; Blokker, B.A. ; Siebelink, E. ; Kok, F.J. ; Afman, L.A. ; Tome, D. ; Mensink, M.R. - \ 2014
The Journal of Nutrition 144 (2014)8. - ISSN 0022-3166 - p. 1174 - 1180.
energy-expenditure - hepatic steatosis - adipose-tissue - liver fat - quantification - disease - rats - homeostasis - accurate - insulin
The objective of this study was to evaluate the effect of increasing protein intake, at the expense of carbohydrates, on intrahepatic lipids (IHLs), circulating triglycerides (TGs), and body composition in healthy humans consuming a high-fat, hypercaloric diet. A crossover randomized trial with a parallel control group was performed. After a 2-wk run-in period, participants were assigned to either the control diet [n = 10; 27.8 energy percent (en%) fat, 16.9 en% protein, 55.3 en% carbohydrates] for 4 wk or a high-fat, hypercaloric diet (n = 17; >2 MJ/d) crossover trial with 2 periods of 2 wk, with either high-protein (HP) (37.7 en% fat, 25.7 en% protein, 36.6 en% carbohydrates) or normal-protein (NP) (39.4 en% fat, 15.4 en% protein, 45.2 en% carbohydrates) content. Measurements were performed after 2 wk of run-in (baseline), 2 wk of intervention (period 1), and 4 wk of intervention (period 2). A trend toward lower IHL and plasma TG concentrations during the HP condition compared with the NP condition was observed (IHL: 0.35 ± 0.04% vs. 0.51 ± 0.08%, P = 0.08; TG: 0.65 ± 0.03 vs. 0.77 ± 0.05 mmol/L, P = 0.07, for HP and NP, respectively). Fat mass was significantly lower (10.6 ± 1.72 vs. 10.9 ± 1.73 kg; P = 0.02) with the HP diet than with the NP diet, whereas fat-free mass was higher (55.7 ± 2.79 vs. 55.2 ± 2.80 kg; P = 0.003). This study indicated that an HP, high-fat, hypercaloric diet affects lipid metabolism. It tends to lower the IHL and circulating TG concentrations and significantly lowers fat mass and increases fat-free mass compared with an NP, high-fat, hypercaloric diet. This trail was registered at www.clinicaltrails.gov as NCT01354626.
Influence of C16:0 and long-chain saturated fatty acids on normal variation of bovine milk fat triacylglycerol structure
Tzompa Sosa, D.A. ; Aken, G.A. van; Hooijdonk, A.C.M. van; Valenberg, H.J.F. van - \ 2014
Journal of Dairy Science 97 (2014)7. - ISSN 0022-0302 - p. 4542 - 4551.
regiospecific analysis - infant formulas - positional distribution - stereospecific analysis - magnesium bromide - palmitic acid - triglycerides - parameters - calcium - rats
Fatty acids (FA) are nonrandomly distributed within milk fat triacylglycerols (TAG). Moreover, the structure of milk fat TAG differs with feeding regimens. So far, nothing is known about the variation of milk fat TAG structure among individual cows. A deep understanding of the normal variation of TAG structures and the relationships between milk fat FA profile and its TAG structure could help to better control functional and compositional differences between milk fats from various sources and to increase the knowledge on milk fat synthesis. The focus of the present study was to determine the regiospecific TAG structure of individual samples of winter milk fat from Dutch Holstein-Friesian cows with a wide variation of FA profiles and with 2 diacylglycerol acyltransferase 1 (DGAT1) genotypes: DGAT1 K232A genotype AA and DGAT1 K232A genotype KK. From an initial set of 1,918 individual milk fat samples, 24 were selected. The selected samples had a wide range of FA composition and had either DGAT1 K232A genotype AA or KK. The structure analysis was done with a regiospecific approach. This analysis is based on the acyl degradation of TAG by a Grignard reagent and further isolation of sn-2 monoacylglycerols by thinlayer chromatography. An intra- and interpositional approach was used to study the structural variation. With the intrapositional approach, the amount of an FA at the secondary (sn-2) and primary (sn-1,3) positions was related to its total amount in the TAG. With the interpositional approach, the proportion of C8:0, C10:0, C14:1 cis-9, C16:1 cis-9, and C18:1 cis-9 at sn-2 was positively correlated with the amount of C16:0 in the triacylglycerol; in contrast, saturated C14:0, C16:0, and long-chain saturated FA (C14:0–C18:0) were negatively correlated. These observations suggest that the amount of long-chain saturated FA in TAG influences the positioning of other FA in the TAG. With an interpositional approach, the DGAT1 polymorphism had a significant effect on the proportional positioning of C16:0 at sn-2. These results provide a new direction to controlling functional and compositional differences between milk fats.
Mature osteoblasts dedifferentiate in response to traumatic bone injury in the zebrafish fin and skull
Geurtzen, K. ; Knopf, F. ; Wehner, D. ; Huitema, L.F.A. ; Schulte-Merker, S. ; Weidinger, G. - \ 2014
Development 141 (2014). - ISSN 0950-1991 - p. 2225 - 2234.
fibroblast-growth-factor - fracture repair - adult zebrafish - lining cells - regeneration - expression - defects - fate - gene - rats
Zebrafish have an unlimited capacity to regenerate bone after fin amputation. In this process, mature osteoblasts dedifferentiate to osteogenic precursor cells and thus represent an important source of newly forming bone. By contrast, differentiated osteoblasts do not appear to contribute to repair of bone injuries in mammals; rather, osteoblasts form anew from mesenchymal stem cells. This raises the question whether osteoblast dedifferentiation is specific to appendage regeneration, a special feature of the lepidotrichia bone of the fish fin, or a process found more generally in fish bone. Here, we show that dedifferentiation of mature osteoblasts is not restricted to fin regeneration after amputation, but also occurs during repair of zebrafish fin fractures and skull injuries. In both models, mature osteoblasts surrounding the injury downregulate the expression of differentiation markers, upregulate markers of the pre-osteoblast state and become proliferative. Making use of photoconvertible Kaede protein as well as Cre-driven genetic fate mapping, we show that osteoblasts migrate to the site of injury to replace damaged tissue. Our findings suggest a fundamental role for osteoblast dedifferentiation in reparative bone formation in fish and indicate that adult fish osteoblasts display elevated cellular plasticity compared with mammalian bone-forming cells.
Effects of polysaccharide from fruiting bodies of Agaricus bisporus, Agaricus brasiliensis, and Phenllinus linteus on alcoholic liver injury
Uyanoglu, M. ; Canbek, M. ; Griensven, L.J.L.D. van; Yamac, M. ; Senturk, H. ; Kartkaya, K. ; Oglakci, A. ; Turgak, O. ; Kanbak, G. - \ 2014
International Journal of Food Sciences and Nutrition 65 (2014)4. - ISSN 0963-7486 - p. 482 - 488.
permeability transition pore - ethanol-induced apoptosis - rats - disease - mushrooms - diets
In the present study, the curative effects of crude polysaccharides (PSs) from mushrooms on the symptoms of alcoholic liver injury were investigated. PSs from Agaricus bisporus, Agaricus brasiliensis, and Phellinus linteus fruiting bodies were administered by gavage at levels of 100¿mg per kg body weight per day for 7¿d after the onset of the disease. The caspase-3 activity, mitochondrial membrane potential, mitochondrial outer membrane integrity of the liver tissues of sacrificed rats, and the serum alanine aminotransferase (ALT) levels were determined. In addition, light and transmission electron microscope (TEM) studies were performed for histopathological and cytological evaluations on liver sections. PSs from A. brasiliensis decreased ALT level and mitochondrial membrane potential and increased the outer membrane integrity; microscopic examinations also revealed normal hepatocytes and tissue. On the basis of our data, it can be argued that crude PSs from Agaricus brasiliensis have therapeutic potential for alcoholic liver injury.
The effect of dietary hydroxyproline and dietary oxalate on urinary oxalate excretion in cats
Dijcker, J.C. ; Plantinga, E.A. ; Thomas, D.G. ; Queau, Y. ; Biourge, V.C. ; Hendriks, W.H. - \ 2014
Journal of Animal Science 92 (2014). - ISSN 0021-8812 - p. 577 - 584.
lactic-acid bacteria - oxalobacter-formigenes - primary hyperoxaluria - feline uroliths - adult cats - calcium - rats - dogs - metabolism - canine
In humans and rodents, dietary hydroxyproline (hyp) and oxalate intake affect urinary oxalate (Uox) excretion. Whether Uox excretion occurs in cats was tested by feeding diets containing low oxalate (13 mg/100g DM) with high (Hhyp-Lox), moderate (Mhyp-Lox), and low hyp (Lhyp-Lox) concentrations (3.8, 2.0 and 0.2 g/100g DM, respectively), and low hyp with high oxalate (93 mg/100g DM; Lhyp-Hox) to 8 adult, female cats in a 48-d study using a Latin square design. Cats were randomly allocated to 1 of the four 12-d treatment periods and fed according to individual energy needs. Feces and urine were collected quantitatively using modified litter boxes during the final 5 d of each period. Feces were analyzed for oxalate and Ca, and urine for specific density, pH, oxalate, Ca, P, Mg, Na, K, ammonia, citrate, urate, sulphate, and creatinine. Increasing hyp intake (0.2, 2.0, and 3.8 g/100g DM) resulted in increased Uox excretion (Lhyp-Lox vs. Mhyp-Lox vs. Hhyp-Lox, P <0.05), and the linear dose-response equation was: Uox (mg ¿d(-1)) = 5.62 + 2.10 x g hyp intake/d (r(2) = 0.56; P <0.001). Increasing oxalate intake from 13 to 93 mg/100g DM did not affect Uox excretion, but resulted in an increase in fecal oxalate output (P <0.001) and positive oxalate balance (32.20 ± 2.06 mg¿d(-1)). The results indicate that the intestinal absorption of the supplemental oxalate, and thereby its contribution to Uox, was low (5.90 ± 5.24%). Relevant increases in endogenous Uox excretion were achieved by increasing dietary hyp intake. The hyp-containing protein sources should be minimized in Ca ox urolith preventative diets until their effect on Uox excretion is tested. The oxalate content (up to 93 mg/100g DM) in a diet with moderate Ca content does not contribute to Uox content.
REG3¿-deficient mice have altered mucus distribution and increased mucosal inflammatory responses to the microbiota and enteric pathogens in the ileum
Loonen, L.M.P. ; Kranenbarg-Stolte, H.H. ; Jaklofsky, M.T.J. ; Meijerink, M. ; Dekker, J. ; Baarlen, P. van; Wells, J. - \ 2014
Mucosal Immunology 7 (2014). - ISSN 1933-0219 - p. 939 - 947.
pancreatitis-associated protein - bacterial aggregation - dietary calcium - bowel-disease - regiii-gamma - expression - salmonella - infection - lectin - rats
REG3¿ is considered to have a protective role against infection with Gram-positive bacteria due to its bactericidal activity, but evidence from in vivo studies is lacking. We generated a REG3¿-/- mouse, and investigated the effect of lack of REG3¿ on intestinal mucus distribution, spatial compartmentalization of bacteria, and expression of innate immunity genes. Infection studies were also performed with Gram-positive and Gram-negative pathogens to investigate the antimicrobial role of REG3¿. REG3¿-/- mice display altered mucus distribution, increased bacterial contact with the epithelium, and elevated inflammatory markers in the ileum without histological evidence of pathology. Infection response pathway genes were differentially expressed in both Listeria monocytogenes and Salmonella enteritidis infected REG3¿-/- and wild-type (wt) mice. Higher amounts of myeloperoxidase and interleukin-22 transcripts were present in the ileal mucosa of REG3¿-/- than wt mice, but translocation to the organs was unaffected. We concluded that REG3¿ has a protective role against mucosal infection with pathogenic Listeria and Salmonella in vivo. REG3¿ is equally distributed throughout the mucus and its absence results in increased epithelial contact with the microbiota resulting in low-grade inflammation. REG3¿ can bind to Gram-negative and Gram-positive bacteria and influence mucus distribution in the ileum, properties which may contribute to mucosal protection.
Bruine rat resistent tegen rattengif : alternatieven zijn dringend gewenst
Schoelitsz, B. ; Meerburg, B.G. - \ 2013
Zoogdier 24 (2013)3. - ISSN 0925-1006 - p. 6 - 8.
fauna - ratten - plaagresistentie - pesticidenwerking - rats - pest resistance - pesticidal action
Overlast door ratten wordt sinds jaar en dag tegengegaan met rodenticiden (beter bekend als rattengif). Ze zijn toegelaten voor de bestrijding van deze knaagdieren. Maar wat als bruine ratten niet meer doodgaan van deze middelen en hiervoor dus resistent zijn? Wat weten we allemaal over resistentie bij deze soort? En wat zijn de consequenties hiervan voor de bestrijding van de bruine rat?
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