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For more than 3 decades, extracorporeal shock wave therapy (ESWT) has been clinically implemented in urologic and orthopaedic indications. Here, we present the case of a patient with envenomation from a highly toxic jellyfish-like siphonophore (Physalia physalis) with a toxic contact dermatitis resulting in chronic eruptive skin lesions. The skin lesions on the dorsal right hand lasted more than 16 weeks and were refractive to local cortisone treatment. They finally healed after 8 applications of low-energy planar/defocused ESWT over 4 weeks. In detail, the clinical course, ESWT specifications and the possible mechanisms of ESWT in the light of the current literature are discussed. Our case indicates that ESWT is an underestimated, promising non-invasive, non-immunosuppressive treatment for chronic eruptive skin lesions after jellyfish or related toxin envenomations.

Propionate has antimicrobial activity and is suggested to influence lipid metabolism. Here, we investigated the effect of propionate on lipid metabolism and the gut microbiome in fructose-fed mice as a model of diet-induced steatosis and gut dysbiosis. Therefore, 48 male wild-type mice were fed isoenergetic diets with either 0% fructose (F-) or 40% fructose (F+) that contained 0% propionate (P-) or 1% propionate (P+) for 7 weeks. Mice that received the F+ diets developed fatty livers, had fewer small intestinal proteobacteria and colonic actinobacteria and were characterised by changes in bacterial genera (e.g.

Insects have rapidly changing energy demands, so they primarily rely on hemolymph and other carbohydrates to carry out life activities. However, how gustatory responsiveness and hemolymph sugar levels coordinate with one another to maintain energetic homeostasis in insects remains largely unknown for the highly social honeybee that goes through large physiological and behavioral changes. The potential role of biogenic amines and neuropeptides in the connection between the regulation of appetite and fluctuating sugar levels in the hemolymph, due to starvation, as the bee ages, was investigated. The largest appetite increase due to the starvation treatment was within the forager age class and this corresponded with an increase in octopamine levels in the brain along with a decline in hemolymph sugar levels. Adipokinetic hormone (AKH) was found in very small quantities in the brain and there were no significant changes in response to starvation treatment. Our findings suggest that the particularly dynamic levels of hemolymph sugar levels may serve as a monitor of the forager honeybee energetic state. Therefore, there may be a pathway in forager bees via octopamine responsible for their precise precipitous regulation of appetite, but to determine cause and effect relationships further investigation is needed.

Plant proteins have become increasingly important for ecological reasons. Rapeseed is a novel source of plant proteins with high biological value, but its metabolic impact in humans is largely unknown. A randomized, controlled intervention study including 20 healthy subjects was conducted in a crossover design. All participants received a test meal without additional protein or with 28 g of rapeseed protein isolate or soy protein isolate (control). Venous blood samples were collected over a 360-min period to analyze metabolites, satiety was assessed using a visual analog scale. Postprandial levels of lipids, urea, and amino acids increased following the intake of both protein isolates. The postprandial insulin response was lower after consumption of the rapeseed protein than after intake of the soy protein (p &lt, 0.05), whereas the postmeal responses of glucose, lipids, interleukin-6, minerals, and urea were comparable between the two protein isolates. Interestingly, the rapeseed protein exerted stronger effects on postprandial satiety than the soy protein (p &lt, 0.05). The postmeal metabolism following rapeseed protein intake is comparable with that of soy protein. The favorable effect of rapeseed protein on postprandial insulin and satiety makes it a valuable plant protein for human nutrition.

Cocoa polyphenols are thought to reduce the risk of cardiovascular diseases. Thus, cocoa-containing foods may have significant health benefits. Here, we studied the impact of chocolate liquor on vascular lesion development and plaque composition in a mouse model of atherosclerosis. Apolipoprotein E (apoE)-knockout mice were assigned to two groups and fed a Western diet that contained 250 g/kg of either chocolate liquor or a polyphenol-free isoenergetic control paste for 16 weeks. In addition to fat, protein, and fibers, the chocolate liquor contained 2 g/kg of polyphenols. Compared with the control group, mice fed the chocolate liquor had larger plaque areas in the descending aorta and aortic root, which were attributed to a higher mass of vascular smooth muscle cells (VSMCs) and collagen. Vascular lipid deposits and calcification areas did not differ between the two groups. The aortic tissue level of interleukin-6 (IL-6) mRNA was 5-fold higher in the mice fed chocolate liquor than in the control mice. Chocolate-fed mice exhibited an increased hepatic saturated to polyunsaturated fatty acid ratio than the controls. Although the chocolate liquor contained 14 µg/kg of vitamin D2, the chocolate liquor-fed mice did not have measurable 25-hydroxyvitamin D2 in the serum. These mice even showed a 25% reduction in the level of 25-hydroxyvitamin D3 compared with the control mice. Overall, present data may contribute to our understanding how chocolate constituents can impact vascular lesion development.

Insects, due to their small size, have limited energy storage space, but they also have high metabolic rate, so their hemolymph sugars are incredibly dynamic and play a number of important physiological functional roles in maintaining energetic homeostasis. In contrast to vertebrates, trehalose is generally the primary sugar found in insect hemolymph, which is followed by glucose and fructose. Many analytical chemistry methods exist to measure sugars, yet a direct comparison of methods that can measure all three simultaneously, and trehalose in particular, from low sample volumes, are sparse. Using the honey bee as a model, we directly compare the leading current methods of using High Performance Liquid Chromatography (HPLC) with an evaporative light-scattering detector and Gas Chromatography coupled with Mass Spectrometry (GC-MS) to determine which method would be better for measuring trehalose, glucose, and fructose in terms of reproducibility, accuracy, and sensitivity. Furthermore, we injected the enzyme inhibitors trehalozin (a trehalase inhibitor) and sorbose (a trehalase p-synthase inhibitor) to manipulate the trehalose levels in honey bee foragers as a proof of concept that this sugar can be altered independently of hemolymph glucose and fructose levels. Overall the HPLC method was less reproducible for measuring fructose and glucose, and it also had lower sensitivity for measuring trehalose. Consequently, significant differences in trehalose levels within the forager class were only detected with the GC-MS and not the HPLC method. Lastly, using the GC-MS method in the follow up study we found that trehalozin and sorbose causes a significant increase and decrease of trehalose levels respectively, in forager honey bees, independent of the glucose and fructose levels, ten minutes after injection. Taken together, these methods will provide useful tools for future studies exploring the many different physiological functional roles that trehalose can play in maintaining insect energetic homeostasis.

Short-chain fatty acids are processed from indigestible dietary fibers by gut bacteria and have immunomodulatory properties. Here, we investigate propionic acid (PA) in multiple sclerosis (MS), an autoimmune and neurodegenerative disease. Serum and feces of subjects with MS exhibited significantly reduced PA amounts compared with controls, particularly after the first relapse. In a proof-of-concept study, we supplemented PA to therapy-naive MS patients and as an add-on to MS immunotherapy. After 2 weeks of PA intake, we observed a significant and sustained increase of functionally competent regulatory T (Treg) cells, whereas Th1 and Th17 cells decreased significantly. Post-hoc analyses revealed a reduced annual relapse rate, disability stabilization, and reduced brain atrophy after 3 years of PA intake. Functional microbiome analysis revealed increased expression of Treg-cell-inducing genes in the intestine after PA intake. Furthermore, PA normalized Treg cell mitochondrial function and morphology in MS. Our findings suggest that PA can serve as a potent immunomodulatory supplement to MS drugs.

Epidemiological studies revealed that dietary proteins can contribute to the modulation of the cardiovascular disease risk. Still, direct effects of dietary proteins on serum metabolites and other health-modulating factors have not been fully explored. Here, we compared the effects of dietary lupin protein with the effects of beef protein and casein on the serum metabolite profile, cardiovascular risk markers and the fecal microbiome. Pigs were fed diets containing 15% of the respective proteins for 4 weeks. A classification analysis of the serum metabolites revealed six biomarker sets of two metabolites each that discriminated between the intake of lupin protein, lean beef or casein. These biomarker sets included 1- and 3-methylhistidine, betaine, carnitine, homoarginine and methionine. The study revealed differences in the serum levels of the metabolites 1- and 3- methylhistidine, homoarginine, methionine and homocysteine, which are involved in the one-carbon cycle. However, these changes were not associated with differences in the methylation capacity or the histone methylation pattern. With the exception of serum homocysteine and homoarginine levels, other cardiovascular risk markers, such as the homeostatic model assessment index, trimethylamine-N-oxide and lipids, were not influenced by the dietary protein source. However, the composition of the fecal microorganisms was markedly changed by the dietary protein source. Lupin-protein-fed pigs exhibited more species from the phyla Bacteroidetes and Firmicutes than the other two groups. In conclusion, different dietary protein sources induce distinct serum metabolic fingerprints, have an impact on the cardiovascular risk and modulate the composition of the fecal microbiome. (C) 2019 Elsevier Inc. All rights reserved.

Growing evidence suggests that disintegrin and metalloprotease (ADAM) 17 (ADAM17) and ADAM10 contribute to the pathogenesis of vascular diseases. ADAM17 promotes inflammatory processes by liberating tumor necrosis factor α, interleukin 6 receptor (IL-6R), and tumor necrosis factor receptor 1 (TNFR1). ADAM17 and ADAM10 modulate vascular permeability by cleaving endothelial adhesion molecules such as junctional adhesion molecule A (JAM-A) and vascular endothelial cadherin (VE-cadherin), respectively.This study was designed to investigate whether a link might exist between the protective effects of fish oil (FO) supplementation against atherosclerosis and ADAM function.Male LDL receptor knockout (LDLR(-/-)) mice and male wild-type (WT) mice were fed a Western diet (200 g/kg fat, 1.5 g/kg cholesterol) containing either 20% lard (LDLR(-/-)-lard and WT-lard groups) or 10% lard combined with 10% FO (LDLR(-/-)-FO and WT-FO groups) for 12 wk. Atherosclerotic lesion development and fatty acid composition of liver microsomes were evaluated. ADAM10 and ADAM17 expression was determined by quantitative real-time polymerase chain reaction and immunoblot analyses. Concentrations of soluble ADAM substrates in plasma and liver extracts were measured by ELISA.Diets supplemented with FO markedly reduced development of early atherosclerotic lesions in LDLR(-/-) mice (LDLR(-/-)-lard group vs. LDLR(-/-)-FO group mean ± SD: 29.6 ± 6.1% vs. 22.5 ± 4.2%, P0.05). This was not accompanied by changes in expression of ADAM17 or ADAM10 in the aorta or liver. No dietary effects on circulating TNFR1 (LDLR(-/-)-lard group vs. LDLR(-/-)-FO group mean ± SD: 1.22 ± 0.23 vs. 1.39 ± 0.28, P0.2) or IL-6R (1.06 ± 0.12 vs. 0.98 ± 0.09 fold of WT-lard group, P0.1), classical substrates of ADAM17 on macrophages, and neutrophil granulocytes were observed. However, a reduction in atherosclerotic lesions in the LDLR(-/-)-FO group was accompanied by a significant reduction in the circulating endothelial cell adhesion molecules JAM-A (LDLR(-/-)-lard group vs. LDLR(-/-)-FO group mean ± SD: 1.42 ± 0.20 vs. 0.95 ± 0.56 fold of WT-lard group, P0.05), intercellular adhesion molecule 1 (1.15 ± 0.14 vs. 0.88 ± 0.17 fold of WT-lard group, P0.05), and VE-cadherin (0.88 ± 0.12 vs. 0.72 ± 0.15 fold of WT-lard group, P0.05), reflecting reduced ADAM activity in endothelial cells.FO exerted an antiatherogenic effect on male LDLR(-/-) mice that was accompanied by a reduced release of ADAM17 and ADAM10 substrates from endothelial cells. It is suggested that FO-decreased ADAM activity contributes to improved endothelial barrier function and thus counteracts intimal lipoprotein insudation and macrophage accumulation.

Short chain fatty acids (SCFA) are processed from indigestible dietary fibers by gut bacteria and have immunomodulatory properties. Here we investigate the SCFA propionic acid (PA) in multiple sclerosis (MS) as a model of general autoimmune and neurodegenerative diseases. The serum and feces of MS patients exhibited significantly reduced PA-levels, which were associated with a reduction in diversity and abundance of SCFA-producing bacteria. In a proof-of-concept study, we supplemented PA to MS patients as add-on to immunotherapy. After two weeks of PA intake, we observed a significant and sustained increase of functionally competent Treg, while Th1 and Th17 significantly decreased. Retrospective analyses of up to 3years of PA-intake revealed a reduced annual relapse rate, stabilization of disability and reduced brain atrophy. In primary neurons, differentiated from MS patient-specific induced pluripotent stem cells, PA enhanced neurite regrowth after damage, similar to the Treg key cytokine interleukin-10. Our findings suggest that PA can serve as a potent immunomodulatory and neuroprotective supplement to approved MS drugs.

cope Several studies have proposed a role of vitamin D in adipogenesis. Here, we sought to study the impact of the vitamin D receptor (Vdr) on adipocyte size in young and old mice and the effect of maternal vitamin D deficiency on fetal adipogenesis. Methods and results Histological analysis of adipose tissues shows that Vdr knockout (KO) mice have smaller adipocytes than wild-type (WT) mice. Next, we compare young and old Vdr-KO and WT mice and find no differences in adipocyte sizes between weaned Vdr-KO and WT mice. However, 1-year-old Vdr-KO mice, suffering from alopecia, have smaller-sized adipocytes than WT mice, although they consume more food. To elucidate whether vitamin D can directly impact adipocyte development at a critical stage of adipogenesis, we feed rat dams a vitamin D deficient (0 IU kg−1) or vitamin D adequate (1000 IU kg−1) diet. Neither DNA microarray analysis of the adipose tissues of the newborn rats nor the adipocyte sizes of 21-day-old offspring show significant differences between the two groups. Conclusion Data indicate that vitamin D does not play a fundamental role in adipogenesis because vitamin D does not affect fetal adipogenesis. Moreover, the smaller adipocytes observed in adult Vdr-KO mice are presumably caused by an increased energy expenditure due to alopecia.

Transforming growth factor-β (TGF-β) is a cytokine produced by many cell types and implicated in cell growth, differentiation, apoptosis, and inflammation. It stimulates store-operated calcium entry (SOCE) through the calcium release-activated calcium (CRAC) channel Orai1/Stim1 in endometrial Ishikawa cells. Bone cells generate fibroblast growth factor (FGF) 23, which inhibits renal phosphate reabsorption and 1,25(OH)2D3 formation in concert with its co-receptor Klotho. Moreover, Klotho and FGF23 counteract aging and age-related clinical conditions. FGF23 production is dependent on Orai1-mediated SOCE and inflammation. Here, we explored a putative role of TGF-β2 in FGF23 synthesis. To this end, UMR106 osteoblast-like cells were cultured, Fgf23 transcript levels determined by qRT-PCR, FGF23 protein measured by ELISA, and SOCE analyzed by fluorescence optics. UMR106 cells expressed TGF-β receptors 1 and 2. TGF-β2 enhanced SOCE and potently stimulated the production of FGF23, an effect significantly attenuated by SB431542, an inhibitor of the transforming growth factor-β (TGF-β) type I receptor activin receptor-like kinases ALK5, ALK4, and ALK7. Furthermore, the TGF-β2 effect on FGF23 production was blunted by SOCE inhibitor 2-APB. We conclude that TGF-β2 induces FGF23 production, an effect involving up-regulation of SOCE.

Food-based strategies need to be developed to improve the vitamin D status of individuals. Recent studies identified ultraviolet B irradiation as an efficient method to enrich mushrooms and eggs with vitamin D. The aim of this study was to determine whether free-range farming of hens could provide a valuable method to produce vitamin D-enriched eggs.Laying hens were randomly assigned to three groups of 33 to 34 animals each, and were kept either indoors (indoor group), outdoors (outdoor group), or with an indoor/outdoor option (indoor/outdoor group) over 4 wk.The study shows that the vitamin D3 content of egg yolk was three- to fourfold higher in the groups that were exposed to sunlight (outdoor and indoor/outdoor groups) compared with the indoor group (P0.001). Egg yolk from the outdoor group revealed the highest vitamin D3 content, which averaged 14.3 μg/100 g dry matter (DM), followed by that from the indoor/outdoor group (11.3 μg/100 g DM). Yolk from indoor eggs contained only 3.8 μg vitamin D/100 g DM. The 25-hydroxyvitamin D (25[OH]D3) content of egg yolk was also influenced by sunlight exposure, although less pronounced than the vitamin D content (P0.05). In contrast, free-range eggs randomly acquired from supermarkets had relatively low vitamin D contents.Free-range farming offers an efficient alternative to fortify eggs with vitamin D, provided that farming conditions are sufficiently attractive for hens to range outside.

Considerable variation in 25-hydroxyvitamin D (25(OH)D) in populations worldwide that seems to be independent of latitude has been reported. Therefore, we aimed to assess vitamin D status of a mid-aged German general population and to identify its dietary, lifestyle, anthropometric, and genetic determinants.25(OH)D concentrations were measured by LC-MS/MS in plasma samples of a random subcohort of the German arm of the European Prospective Investigation into Cancer and Nutrition (EPIC) comprising 2,100 subjects aged 35-65 years. Associations between potential predictors and 25(OH)D were assessed by linear regression models.32.8% of the variance in 25(OH)D was explained by a multivariable regression model, with season being the by far strongest predictor (semi-partial R²: 14.6%). Sex, waist circumference, leisure time physical activity, smoking, polymorphisms in the GC, CYP2R1, and DHCR7 genes, supplement use, exogenous hormone use, alcohol consumption, egg consumption, and fish consumption were significantly associated with 25(OH)D concentrations as well. However, none of these factors explained2.3% of the variance in 25(OH)D.Even with a comprehensive set of genetic, anthropometric, dietary, and lifestyle correlates, not more than 32.8% of the variation in 25(OH)D could be explained in the EPIC-Germany study, implying that vitamin D prediction scores may not provide an appropriate proxy for measured 25(OH)D. Food intake was only a weak predictor of 25(OH)D concentrations, while a strong seasonal fluctuation in 25(OH)D was shown.

Background Treatment of hyperlipidemic patients with fibrates, agonists of peroxisome proliferator-activated receptor α (PPARα), provokes muscle atrophy as a side effect. The molecular mechanism underlying this phenomenon is still unknown. We tested the hypothesis that activation of PPARα leads to an up-regulation of the ubiquitin proteasome system (UPS) which plays a major role in protein degradation in muscle. Methods Rats, wild-type and PPARα-deficient mice (PPARα−/−) were treated with synthetic PPARα agonists (clofibrate, WY-14,643) to study their effect on the UPS and myofibrillar protein breakdown in muscle. Results In rats and wild-type mice but not PPARα−/− mice, clofibrate or WY-14,643 caused increases in mRNA and protein levels of the ubiquitin ligases atrogin-1 and MuRF1 in muscle. Wild-type mice treated with WY-14,643 had a greater 3-methylhistidine release from incubated muscle and lesser muscle weights. In addition, wild-type mice but not PPARα−/− mice treated with WY-14,643 had higher amounts of ubiquitin–protein conjugates, a decreased activity of PI3K/Akt1 signalling, and an increased activity of FoxO1 transcription factor in muscle. Reporter gene and gel shift experiments revealed that the atrogin-1 and MuRF1 promoter do not contain functional PPARα DNA-binding sites. Conclusions These findings indicate that fibrates stimulate ubiquitination of proteins in skeletal muscle which in turn stimulates protein degradation. Up-regulation of ubiquitin ligases is probably not mediated by PPARα-dependent gene transcription but by PPARα-dependent inhibition of the PI3K/Akt1 signalling pathway leading to activation of FoxO1. General significance PPARα plays a role in the regulation of the ubiquitin proteasome system.

To combat vitamin D insufficiency in a population, reliable diet sources of vitamin D are required. The recommendations to consume more oily fish and the use of UVB treated yeast are already applied strategies to address vitamin D insufficiency. This study aimed to elucidate the suitability of plant oils as an alternative vitamin D source. Therefore, plant oils that are commonly used in human nutrition were firstly analyzed for their content of vitamin D precursors and metabolites. Secondly, selected oils were exposed to a short-term UVB irradiation to stimulate the synthesis of vitamin D. Finally, to elucidate the efficacy of plant-derived vitamin D to improve the vitamin D status, we fed UVB-exposed wheat germ oil for 4 weeks to mice and compared them with mice that received non-exposed or vitamin D3 supplemented wheat germ oil. Sterol analysis revealed that the selected plant oils contained high amounts of ergosterol, but also 7-dehydrocholesterol (7-DHC), with the highest concentrations found in wheat germ oil. Exposure to UVB irradiation resulted in a partial conversion of ergosterol and 7-DHC to vitamin D2 and D3 in these oils. Mice fed the UVB-exposed wheat germ oil were able to improve their vitamin D status as shown by the rise in the plasma concentration of 25 hydroxyvitamin D (25(OH)D) and the liver content of vitamin D compared to mice fed the non-exposed oil. However, the plasma concentration of 25(OH)D of mice fed the UVB-treated oil did not reach the values observed in the group fed the D3 supplemented oil. It was striking that the intake of the UVB-exposed oil resulted in distinct accumulation of vitamin D2 in the livers of these mice. In conclusion, plant oils, in particular wheat germ oil, contain considerable amounts of vitamin D precursors which can be converted to vitamin D via UVB exposure. However, the UVB-exposed wheat germ oil was less effective to improve the 25(OH)D plasma concentration than a supplementation with vitamin D3.

1. The effects of n-3 polyunsaturated fatty acids (PUFA) and conjugated linoleic acids (CLA) on genes involved in carnitine homeostasis were compared in laying hens. Three groups of laying hens were fed on a control diet or a diet with either 3% of fish oil or CLA for 4 weeks. 2. Feed intake and egg production rate did not differ between the three groups. Diets with fish oil or CLA had only a weak effect on mRNA levels of PPARα target genes (ACO, CPT-I) in the liver and did not influence mRNA concentrations of the most important carnitine transporter OCTN2, enzymes of involved in carnitine synthesis (TMLD, TMABA-DH, BBD) or concentrations of carnitine in plasma, liver and total egg contents. 3. Hens fed the CLA diet had lower concentrations of free and total carnitine in egg yolk but higher concentrations of carnitine in albumen than control hens (P 0·05), whereas the amount of free and total carnitine in whole egg did not differ. 4. In conclusion, the study showed that feeding fish oil or CLA causes only a weak activation of PPARα in tissues of laying hens that probably explained the lack of effect on carnitine homeostasis. The results contrast with those in humans and mice that show a significant effect of synthetic PPARα agonists on carnitine homeostasis in humans and mice.

Scope: Metabolic stress induced by chronic high-fat (HF) diet feeding or genetically induced diabetes impairs carnitine status. Herein, we tested the hypothesis that regular endurance exercise (EE) improves the HF diet-induced impairment of carnitine status through stimulating the expression of hepatic genes involved in carnitine synthesis and uptake. Methods and results: Eighteen male C57BL/6 mice were assigned to three groups: group S received a standard diet, group HF received a HF diet, and group HF1EE received an HF diet and was regularly exercised on a treadmill. After 10wk, mice of the HF and the HF1EE groups were highly obese and insulin resistant compared with mice of the S group (po0.05), but mice of the HF1EE group were less insulin resistant than those of the HF group (po0.05). The HF group had lower carnitine concentrations and mRNA and protein levels of genes involved in carnitine synthesis and uptake in the liver than the S group (po0.05), whereas these parameters did not differ between the S group and the HF1EE group. Conclusion: These findings indicate that regular EE reverses an HF diet-induced impairment of hepatic carnitine content by stimulating hepatic carnitine synthesis and uptake.

We studied a model system consisting of Sorghum bicolor , phenanthrene, and an auxin-producing polycyclic aromatic hydrocarbon-degrading Sinorhizobium meliloti strain to clarify whether rhizosphere indole-3-acetic acid (IAA) takes part in the plant–pollutant–bacteria interactions. Phenanthrene and S. meliloti treatments of sorghum contributed to a decrease in the rhizosphere IAA concentration and to phytohormone accumulation, respectively. Regression analysis showed significant correlations between alteration in root-zone IAA content and alterations in the root-surface area, exudation, and rhizosphere effects for culturable heterotrophic bacteria, the S. meliloti strain, and other phenanthrene degraders. According to the data obtained, phenanthrene degraders get an advantage over nondegradative rhizobacteria from IAA for rhizosphere colonization. An IAA-dependent increase in the root-surface area leads to improved sorghum growth under pollutant stress. The carbon flux from the roots is corrected by the auxin because of its influence on the exuding-surface area and on the intensity of secretion by the root cells. On the other hand, the rhizosphere IAA pool may be plant-regulated by means of alteration in carboxylate exudation and its influence on bacterial auxin production. A scenario for the IAA-mediated S. bicolor –phenanthrene– S. meliloti interactions is proposed.

Inconsistent results exist from human and animal studies for Se and methionine (Met) regarding their influence on homocysteine (HCys) and cholesterol (Chol) metabolism. To elucidate these contradictions, sixty-four weanling albino rats were divided into eight groups of 8, and were fed diets containing four different Se levels (15, 50, 150 and 450 μg/kg) either in combination with the recommended Met level of 3 g/kg (C15, C50, C150 and C450) or with an increased Met concentration of 15 g/kg (M15, M50, M150 and M450) for 8 weeks. Plasma HCys was twofold higher in the Se-supplemented C groups than in group C15. Met addition also doubled plasma HCys compared with the respective C groups. In contrast, the expression of the key enzymes of glutathione biosynthesis in the liver was significantly lowered by Se and in particular by Met. Liver Chol concentration was significantly higher in all the Se-supplemented C and M groups than in groups C15 and M15. Plasma Chol was, however, lowered. The uninfluenced expression of sterol-regulatory element-binding protein 2 and of hydroxymethyl-glutaryl-CoA reductase, the increased LDL receptor expression and the reduced expression of the hepatobiliary Chol exporter ATP-binding-cassette-transporter 8 (ABCG8) by Se and/or Met explain these findings. We conclude that the elevation of plasma HCys in rats by Se and Met results from a higher export into plasma. The fact that Se in particular combined with Met increases liver Chol but reduces plasma Chol should be addressed in future investigations focussing on the regulation of ABCG8, which is also selectively involved in the reverse transport of phytosterols in the small intestine.

In rodents, fasting increases the carnitine concentration in the liver by an up-regulation of enzymes of hepatic carnitine synthesis and novel organic cation transporter (OCTN) 2, mediated by activation of peroxisome proliferator-activated receptor (PPAR) alpha. This study was performed to investigate whether such effects occur also in pigs which like humans, as nonproliferating species, have a lower expression of PPARalpha and are less responsive to treatment with PPARalpha agonists than rodents. An experiment with 20 pigs was performed, which were either fed a diet ad-libitum or fasted for 24 h. Fasted pigs had higher relative mRNA concentrations of the PPARalpha target genes carnitine palmitoyltransferase 1 and acyl-CoA oxidase in liver, heart, kidney, and small intestinal mucosa than control pigs, indicative of PPARalpha activation in these tissues (P

Protein from lupin is supposed to have anti-atherogenic effects due to its lipid-lowering properties in laboratory animals. It is further suggested that the amino acid cysteine plays a crucial role in this aspect. The objective of the present study was to compare the effects of lupin protein and cysteine-supplemented casein with those of casein on atherosclerotic lesion development in apoE-deficient mice. For that purpose, thirty mice were fed an egg albumin-based Western-type diet containing test protein (100 g/kg) for 4 months. ApoE-deficient mice fed the lupin protein or the cysteine-supplemented casein had more than 50 % less aortic calcification than mice fed casein (P P

In contrast to other species, less is known about carnitine homeostasis in the pig. This study was performed to yield information about the site of carnitine synthesis and carnitine concentrations in various tissues of pigs (Sus scrofa). We found that among several pig tissues, a considerable activity of gamma-butyrobetaine dioxygenase (BBD), the last enzyme of carnitine synthesis, exists, like in humans and several other species, only in liver and kidney. Activity of that enzyme in liver and kidney was lower at birth than in the subsequent weeks of life. Highest carnitine concentrations were found in skeletal muscle and heart. Carnitine concentrations in plasma, liver and kidney at birth were higher than in the subsequent weeks of life in spite of the low BBD activity at birth. In conclusion, this study shows that liver and kidney are the major sites of carnitine synthesis and that neonatal pigs do not have an insufficient carnitine status.

Activation of PPARalpha by clofibrate has recently been shown to cause upregulation of the high-affinity carnitine transporter novel organic cation transporter (OCTN) 2 in small intestine. This strongly suggests that PPARalpha activation in response to clofibrate treatment improves the absorption of carnitine from the diet. To test this hypothesis, we performed an experiment with rats which were fed diets with or without 5 g clofibrate/kg diet and with or without 5 g L-carnitine/kg diet. PPARalpha was significantly activated by clofibrate in small intestine as evidenced by increased relative mRNA concentrations of the PPARalpha target gene acyl-CoA oxidase (P0.05). Relative mRNA concentration of OCTN2 in small intestine was significantly increased by clofibrate (P0.05) but not the carnitine supplementation, whereas relative mRNA concentrations of other carnitine transporters (OCTN1, ATB(0+)) in small intestine were not influenced by either clofibrate or carnitine. The absorption rate of carnitine in small intestine was markedly higher in rats treated with clofibrate than in those treated without clofibrate (P0.05). In conclusion, the present study shows that administration of clofibrate to rats increases carnitine absorption in small intestine which is probably due to the observed upregulation of OCTN2 mediated by activation of PPARalpha.

Recent studies have shown that treatment of rodents with agonists of peroxisome proliferator-activated receptor (PPAR)-alpha causes an up-regulation of novel organic cation transporter (OCTN)-2, a carnitine transporter, and increases carnitine concentration in the liver. This study was performed to investigate whether such effects occur also in pigs which like humans have a lower expression of PPAR alpha and are less responsive to treatment with PPAR alpha agonists than rodents. An experiment with 18 pigs was performed which were fed a control diet or the same diet supplemented with 5 g clofibrate/kg for 28 days. Pigs treated with clofibrate had higher relative mRNA concentrations of OCTN2 in liver (3.1-fold), skeletal muscle (1.5-fold) and epithelial cells from small intestine (1.8-fold) than control pigs (P

Background/Aim: Protein-associated amino acids are supposed to play a role in sterol regulatory element-binding protein (SREBP)-mediated regulation of lipid metabolism. This study investigates the effects of cysteine on expression of SREBP-regulated hepatic genes. Methods: HepG2 cells which are an accepted model for the study of the lipid metabolism were treated with L-cysteine under different conditions. Results: Exposure of cells to L-cysteine reduced the mRNA concentrations of SREBP-1c (–35 to –43%) and its target genes fatty acid synthase (FAS; –20 to –50%), glucose-6-phosphate-dehydrogenase (G6PDH; –31 to –35%), and stearoyl-coenzyme A desaturase (SCD)1 (–34 to –50%). Cells treated with L-cysteine had 47% higher glutathione and 47% lower triglyceride concentrations than control cells. In cells which were concurrently treated with L-cysteine and L-buthionine-[S,R]-sulfoximine, an inhibitor of enzymatic glutathione synthesis, no down-regulation of the gene expression was observed. Pro-oxidant CuSO4 up-regulated SREBP-1c (+71%), FAS (+165%), G6PDH (+84%) and SCD1 (+96%) mRNA abundance compared to control cells, but when cells were concurrently treated with L-cysteine, the gene expression remained at control level. Conclusions: The results show that L-cysteine rapidly down-regulates the transcription of genes involved in fatty acid biosynthesis via a mechanism that appears to be mediated by an improved glutathione status.

Background: Recently, we have shown that activation of peroxisome proliferator-activated receptor (PPAR)-α by clofibrate leads to an upregulation of novel organic cation transporter (OCTN)-2, a carnitine transporter, and in turn increases the carnitine concentration in the liver of rats. In this study, we tested the hypothesis that fasting and caloric restriction, conditions under which PPARα activation also occurs, cause similar effects. Methods: Three groups of rats received the diet either ad libitum (control rats) or 10.5 g diet/day (70% of energy requirement for maintenance, E70 rats) or 6 g diet/day (40% of energy requirement for maintenance, E40 rats) for 10 days. A 4th group received the diet ad libitum for 9 days and was then fasted for 24 h (fasted rats). Results: Fasted and calorie-restricted rats had increased mRNA concentrations of acyl-CoA oxidase and carnitine palmitoyltransferase-1 in the liver, heart and kidneys compared to control rats (p < 0.05), indicative of activation of PPARα in these tissues. E70 rats had increased OCTN2 mRNA concentrations in liver (2.6-fold) and kidneys (1.5-fold) and increased total carnitine concentrations in these tissues compared to control rats. E40 rats had increased OCTN2 mRNA concentrations in the liver (3.3-fold), skeletal muscle (2.2-fold), heart (2.3-fold) and kidneys (3.5-fold) and increased total carnitine concentrations in these four tissues compared to control rats. Fasted rats had increased OCTN2 mRNA concentrations in the liver (4.0-fold), heart (2.1-fold) and kidneys (2.0-fold) and increased total carnitine concentrations in these three tissues (p < 0.05). Conclusion: The study shows that fasting and caloric restriction lead to an upregulation of OCTN2 in several tissues, probably mediated by activation of PPARα. Increased tissue carnitine concentrations in fasted and calorie-restricted rats might be at least in part due to increased uptake of carnitine by OCTN2.

International audience; Host-pathogen coevolution leads to reciprocal adaptations, allowing pathogens to increase host exploitation or hosts to minimise costs of infection. As pathogen resistance is often associated with considerable costs, tolerance may be an evolutionary alternative. Here, we examined the effect of two closely related and highly host dependent intracellular gut pathogens, Nosema apis and Nosema ceranae, on the energetic state in Nosema tolerant and sensitive honeybees facing the infection. We quantified the three major haemolymph carbohydrates fructose, glucose, and trehalose using highperformance liquid chromatography (HPLC) as a measure for host energetic state. Trehalose levels in the haemolymph were negatively associated with N. apis infection intensity and with N. ceranae infection regardless of the infection intensity in sensitive honeybees. Nevertheless, there was no such association in Nosema spp. infected tolerant honeybees. These findings suggest that energy availability in tolerant honeybees was not compromised by the infection. This result obtained at the individual level may also have implications at the colony level where workers in spite of a Nosema infection can still performaswell as healthy bees, maintaining colony efficiency and productivity.

In addition to its role as an essential protein component, leucine (Leu) displays several other metabolic functions such as activation of protein synthesis. This property makes it an interesting amino acid for the therapy of human muscle atrophy and for livestock production. However, Leu can stimulate its own degradation via the branched-chain keto acid dehydrogenase complex (BCKDH). To examine the response of several tissues to excessive Leu, pigs were fed diets containing two- (L2) and four-fold (L4) higher Leu contents than the recommended amount (control). We found that the L4 diet led to a pronounced increase in BCKDH activity in the brain (2.5-fold, P < 0.05), liver (1.8-fold, P < 0.05) and cardiac muscle (1.7-fold, P < 0.05), whereas we found no changes in enzyme activity in the pancreas, skeletal muscle, adipose tissue and intestinal mucosa. The L2 diet had only weak effects on BCKDH activity. Both high Leu diets reduced the concentrations of free valine and isoleucine in nearly all tissues. In the brain, high Leu diets modified the amount of tryptophan available: for serotonin synthesis. Compared to the controls, pigs treated with the high Leu diets consumed less food, showed increased plasma concentrations of 3-hydroxybutyrate and reduced levels of circulating serotonin. In conclusion, excessive Leu can stimulate BCKDH activity in several tissues, including the brain. Changes in cerebral tryptophan, along with the changes in amino acid-derived metabolites in the plasma may limit the use of high Leu diets to treat muscle atrophy or to increase muscle growth.

Activation of PPARalpha by clofibrate has recently been shown to cause upregulation of carnitine transporter organic cation transporter (OCTN) 2 and elevated carnitine concentrations in rat liver. The present study has been conducted to further explore the effect of clofibrate on OCTN expression, carnitine biosynthesis, and carnitine accumulation in different rat tissues, and thus two groups of rats were fed diets containing 0.5% clofibrate or 0% clofibrate (control group). PPARalpha-responsive genes were markedly upregulated in the liver (P

The present study investigated whether treatment of female rats with pivalate affects their reproductive function. Therefore, two experiments with female rats were performed. The first experiment included two groups of rats which received drinking water without (control) or with 20 mmol pivalate/L. The second experiment included a control group (which received drinking water without pivalate and a diet without added carnitine) and four groups which received drinking water with 20 mmol/L pivalate and diets without or with 1, 3 or 5 g added carnitine/kg, respectively. In both experiments, rats treated with pivalate had a lower number of pups born alive and, as a consequence of this, lower litter weights than control rats (p0.05); pup weights were not altered by pivalate treatment. Supplementation of dietary carnitine in Experiment 2 increased plasma and tissue carnitine concentration even in excess of those in control rats but did not restore normal litter sizes. This study shows for the first time that pivalate affects the reproductive function in female rats independent of its effect on the carnitine status.

Soy intake acts hypolipidemically. Besides isoflavones, soy protein itself is suggested to influence plasma lipid concentrations. We investigated the effects of an alcohol-washed isoflavone-poor soy protein isolate on plasma and liver lipids and the hepatic expression of genes encoding proteins involved in cholesterol and fatty acid metabolism. Therefore, rats were fed diets containing 200 g/kg of either ethanol-extracted soy protein isolate or casein over 22 days. Rats fed soy protein isolate had markedly lower concentrations of liver cholesterol and lower concentrations of triglycerides in the liver and in plasma than rats fed casein (P.05). Rats fed soy protein isolate had lower relative mRNA concentrations of sterol-regulatory element-binding protein (SREBP)-2, 3-hydroxy-3-methylglutaryl coenzyme A reductase, low-density lipoprotein receptor, cholesterol 7alpha-hydroxylase, apolipoprotein B, Delta9-desaturase and glucose-6-phosphate dehydrogenase in the liver than rats fed casein (P.05). Hepatic mRNA concentration of SREBP-1c tended to be lower in rats fed soy protein isolate (P.10). Hepatic mRNA concentrations of insulin-induced gene (Insig) 1 and Insig-2 and of microsomal triglyceride transfer protein, as well as plasma concentrations of free fatty acids, insulin and glucagon, were not different between the two groups. In conclusion, this study suggests that isoflavone-poor soy protein isolate affects cellular lipid homeostasis by the down-regulation of SREBPs and its target genes in the liver, which are involved in the synthesis of cholesterol and triglycerides.

Background: Recently, it has been shown that dietary lupin protein lowers plasma triglyceride concentrations in rats. In this study, we investigated the hypothesis that this effect is due to a downregulation of sterol regulatory element-binding protein (SREBP)-1c, a transcription factor that regulates the expression of lipogenic enzymes in the livers of rats. Methods: Two groups of 12 rats each were fed semisynthetic diets containing 200 g/kg of either casein (control group) or lupin protein from Lupinus albus for 22 days. Results: Rats fed the diet containing lupin protein had lower concentrations of triglycerides in the liver, plasma and VLDL + chylomicrons (p < 0.05). The concentration of protein in VLDL + chylomicrons was also lower in rats fed lupin protein than in rats fed casein (p < 0.05). The mRNA concentrations of SREBP-1c and fatty acid synthase in the liver were lower in rats fed lupin protein than in rats fed casein (p < 0.05). The mRNA concentrations of lipoprotein lipase in the liver did not differ between both groups of rats. Conclusion: This study confirms that a protein isolated from L. albus is strongly hypotriglyceridemic in rats. It is shown for the first time that this effect is at least in part due to a downregulation of SREBP-1c in the liver which in turn leads to a reduction in hepatic fatty acid synthesis.

Objective We assessed the effect of dietary proteins isolated from beef, pork, and turkey meat on concentrations of cholesterol and triacylglycerols in plasma, lipoproteins, and liver and the composition of the microsomal membrane (fatty acids, phosphatidylcholine/phosphatidylethanolamine ratio) compared with that of casein and soy protein in rats. Methods Five groups of 12 rats each were fed semisynthetic diets for 20 d that contained 200 g/kg of proteins isolated from beef, pork, or turkey meat or, as controls, casein or soy protein. Results Rats fed beef, pork, or turkey proteins did not differ in cholesterol concentrations of plasma, lipoproteins, and liver and in composition of microsomal membrane from rats fed the casein diet. All groups fed a protein from an animal source had higher very low-density lipoprotein (VLDL) and liver cholesterol concentrations than did rats fed soy protein. However, rats fed pork protein had lower concentrations of triacylglycerols in liver, plasma, and VLDL and lower mRNA concentrations of sterol regulatory element binding protein-1 and glucose-6-phosphate dehydrogenase than did rats fed casein. However, concentrations of plasma and VLDL triacylglycerols in rats fed pork protein were not as low as those observed in rats fed soy protein. Conclusion Proteins isolated from beef, pork, or turkey meat do not differ from casein in their effects on cholesterol metabolism. Pork protein decreases plasma triacylglycerol concentrations compared with casein but not compared with soy protein. The triacylglycerol-lowering effect of pork protein compared with casein is suggested to be caused by decreased hepatic fatty acid synthesis.

It has been shown that clofibrate treatment increases the carnitine concentration in the liver of rats. However, the molecular mechanism is still unknown. In this study, we observed for the first time that treatment of rats with the peroxisome proliferator activated receptor (PPAR)-alpha agonist clofibrate increases hepatic mRNA concentrations of organic cation transporters (OCTNs)-1 and -2 which act as transporters of carnitine into the cell. In rat hepatoma (Fao) cells, treatment with WY-14,643 also increased the mRNA concentration of OCTN-2. mRNA concentrations of enzymes involved in carnitine biosynthesis were not altered by treatment with the PPARalpha agonists in livers of rats and in Fao cells. We conclude that PPARalpha agonists increase carnitine concentrations in livers of rats and cells by an increased uptake of carnitine into the cell but not by an increased carnitine biosynthesis.

Cholesterol synthesis in animal cells is regulated by sterol regulatory element-binding protein (SREBP)-2. The objective of this study was to investigate whether activation of peroxisome proliferator-activatedreceptor (PPAR)-gamma influences the SREBP-2 dependent cholesterol synthesis in liver and intestinal cells. Therefore, HepG2 and Caco-2 cells were incubated with and without 10 or 30 microM of troglitazone, a synthetic PPAR gamma agonist, for 4 hrs. Incubation with 10 or 30 microM of troglitazone caused a significant, dose-dependent reduction of cholesterol synthesis in both HepG2 and Caco-2 cells (P < 0.05). HepG2 and Caco-2 cells incubated with 10 or 30 microM of troglitazone had also lower mRNA concentrations and lower nuclear protein concentrations of SREBP-2 than untreated control cells (P < 0.05). mRNA concentrations of the SREBP-2 target genes HMG-CoA reductase and LDL receptor were also reduced in HepG2 and Caco-2 cells treated with 30 microM of troglitazone compared to control cells (P < 0.05). In conclusion, this study shows that PPAR gamma activation by troglitazone lowers the cholesterol synthesis in HepG2 and Caco-2 cells by reducing the concentration of nuclear SREBP-2 and successive downregulation of its target genes involved in cholesterol synthesis.

In rats, clofibrate acts as a microsomal enzyme inducer and disrupts the metabolism of thyroid hormones by increasing hepatic glucuronidation of thyroxine. Whether similar effects occur in the pig has not yet been investigated. This study was performed to investigate the effect of clofibrate treatment on metabolism of thyroid hormones in pigs. To this end, an experiment with 18 pigs, which were assigned to two groups, was performed. One group received a control diet, and the other group was fed the same diet supplemented with 5 g of clofibrate/kg for 28 days. Pigs treated with clofibrate had higher hepatic activities of T(3)- and T(4)-UDP glucuronosyltransferases (UGT) and lower concentrations of total and free T(4) and total T(3) in plasma than control pigs (P < 0.05). Weights and histology of the thyroid gland (epithelial height, follicle lumen diameter) did not differ between the two groups, but pigs treated with clofibrate had higher mRNA concentrations of various genes in the thyroid responsive to thyroid-stimulating hormone (TSH) such as TSH receptor, sodium iodine symporter, thyroid peroxidase, and cathepsin B than control pigs (P < 0.05). Pigs treated with clofibrate also had lower hepatic mRNA concentrations of proteins involved in plasma thyroid hormone transport [thyroxine-binding globulin (P < 0.10), transthyretin (P < 0.05), and albumin (P < 0.05)] and thyroid hormone receptor alpha(1) (P < 0.05) than control pigs. In conclusion, this study shows that clofibrate treatment induces a strong activation of T(3)- and T(4)-UGT in pigs, leading to increased glucuronidation and markedly reduced plasma concentrations of these hormones, accompanied by a moderate stimulation of thyroid function.

Background and Aims: Dietary methionine affects cholesterol metabolism in growing rats. Methionine effects on adult rats and mechanisms by which methionine alters the lipid metabolism are not fully elucidated. We investigated possible mechanisms by which dietary methionine acts on lipid metabolism of adult rats. Methods: Male adult rats were divided into three groups (n = 10) and were fed casein-based diets differing in methionine concentration (low-methionine diet: 0.96 g/kg; adequate-methionine diet: 2.22 g/kg, high-methionine diet: 6.82 g/kg) for 4 weeks. Concentrations of triacylglycerols and cholesterol in plasma and lipoproteins, concentration of homocysteine in plasma, concentration of cholesterol in liver, fecal lipid excretion, expression of hepatic HMG-CoA reductase, phosphatidylethanolamine N-methyltransferase 2 (PEMT-2) and of LDL receptor were measured. Results: Rats fed the high-methionine diet had higher plasma homocysteine concentrations than rats fed the low-methionine diet (p < 0.05). Although concentrations of cholesterol in plasma and lipoproteins were not different between the groups, there was a distinct positive correlation between circulating plasma homocysteine and plasma cholesterol (R2 = 0.55, p < 0.001). The fecal excretion of cholesterol and bile acids was not altered by dietary methionine. The relative mRNA concentration of HMG-CoA reductase and of LDL receptor remained unaffected by dietary methionine. Gene expression of PEMT-2 was higher in rats fed the high-methionine diet than in rats fed the other diets (p < 0.05). Conclusion: The results demonstrate that dietary methionine contributes to a rise in circulating homocysteine concentration which positively correlates with the concentration of plasma cholesterol. However, the effects of methionine on cholesterol metabolism of adult rats were relatively weak.

Ten diets (196 g CP and 13.0 MJ ME(N)/kg) with graded levels of tryptophan (Trp) between 0.9 and 2.7 g/kg were offered ad libitum to Ross broilers from day 8-21 post-hatch. Each diet was allocated to three pens of ten birds each. In addition to growth and feed conversion, the accretions of protein, Trp, fat, and energy were determined by comparative whole body analyses. A sigmoidal function was fitted to the data. Responses to Trp supply were nonlinear and attained plateau values (y(max)) within the studied range of Trp supply. The Y(max) values estimated for BW gain, whole body protein gain, and Trp gain during the 14 days under study were 615, 104, and 0.87 g/bird, respectively. Based on the response in whole body protein gain, the estimated requirement was 1.9 g Trp/kg of diet or 0.15 g Trp/MJ of MEN. Estimates made from the other response criteria were similar to this value. While the protein concentration in gained BW was unaffected by Trp intake (169 g of protein per kg of gained BW), fat and energy concentrations of gained BW increased with increasing Trp supply, approaching plateau values of 146 g fat and 9.8 MJ energy per kg of gained BW. This is supposed to result from feed intake increasing with Trp supplementation. The Trp concentration in gained whole body protein (0.84 g Trp/ 16 g of gained N) was not significantly affected by Trp intake. As long as Trp intake was the limiting factor, 59% of supplemented Trp was transferred to gained whole body protein. During the 14 days of the study, broilers inevitably lost 87 mg Trp. This is equivalent to a daily loss of 30 mg/kg BW or a maintenance requirement of 52 mg/kg BW per day. Data determined for the individual factors may be used for future modelling of broilers' Trp requirement.

The present study was performed to investigate the effect of dietary fat and vitamin E on concentrations of cholesterol oxidation products (COP) in broiler muscle. A total of 144 1-d-old broiler chicks were fed diets with either palm oil, soyabean oil or linseed oil and vitamin E concentrations of 20, 40 or 200 mg/kg for 35 d. COP concentrations were analysed in raw, heat-processed (180°C, 20 min) and frozen-stored (−20°C, 6 months) breast and thigh muscles. COP concentrations were influenced by dietary vitamin E concentration, dietary fat, treatment and type of muscle (P

Oxidized fats affect animal metabolism in several ways. To gain a comprehensive understanding of the molecular mechanisms underlying the effects of dietary oxidized fats in rats at varying dietary vitamin E concentrations, the gene expression profile of the liver was monitored with an array containing 1176 binding sites for cDNAs. Rats were fed diets with a fresh fat and vitamin E concentrations of 25 or 250 mg alpha-tocopherol/kg (FF25, FF250 rats) or a fat heated at 50 degrees C for 38 d, with vitamin E concentrations of 25 or 250 mg alpha-tocopherol/kg (OF25, OF250 rats) for 63 d. Differences in gene expression were considered to be significant at a ratio of at least 1.4. In the OF25 rats, the expression of 47 genes was altered; in the OF250 rats, the expression of 37 genes was altered, and in the FF250 rats, the expression of 21 genes was altered compared with FF25 rats. In both OF25 and OF250 rats, a series of target genes of the peroxisome proliferator-activated receptor alpha (PPAR alpha) was upregulated. Determination of gene expression of acyl CoA oxidase and activity of catalase confirmed that oxidized fats caused peroxisome proliferation in the liver. In OF25 and OF250 rats, there was also upregulation of 12 and 5 genes involved in xenobiotic metabolism and stress response, of 7 and 7 genes involved in protein metabolism, of 5 and 2 genes encoding intracellular effectors or modulators and of 5 and 6 genes, respectively, encoding activators or repressors of transcription or translation. In conclusion, this study provides indirect evidence that dietary oxidized fats cause an activation of the PPAR alpha, irrespective of the dietary vitamin E concentration. Identification of several other differentially regulated genes may be helpful to understand the effects of oxidized fats on animal metabolism.

This study was undertaken to investigate the effect of dietary oxidized fats on the relative mRNA concentrations and the activities of fatty acid synthase (FAS) and glucose-6-phosphate dehydrogenase (G6PDH) in the liver of rats treated with vitamin E or selenium. Two experiments with male Sprague-Dawley rats were carried out. The first experiment included eight groups of rats fed diets with either fresh fat or three different types of oxidized fat, prepared by heating at temperatures of 50, 105, or 190 degrees C, over a period of 6 wk. The diets contained either 25 or 250 mg alpha-tocopherol equivalents per kg. The second experiment included four groups of rats fed diets with fresh fat or oxidized fat, heated at a temperature of 55 degrees C, containing either 70 or 570 microg selenium per kg, over a period of 8 wk. Feeding the diets with oxidized fats led to a significant overall reduction of the relative mRNA concentrations and the activities of FAS and G6PDH in both experiments. The effects of the oxidized fats on mRNA concentrations and activities of these enzymes were independent of the dietary concentrations of vitamin E or selenium. Moreover, in both experiments the rats whose diet contained the oxidized fats had significantly lower concentrations of TG in liver, plasma, and VLDL than the rats whose diet contained fresh fat. The study suggests that oxidized fats contain substances that suppress gene expression of lipogenic enzymes in the liver.

Conglutin γ and phytate are considered as potential biofunctional compounds of lupin protein isolate, but their impact on vascular health is unknown. This study aimed to investigate the effect of conglutin γ and phytate, respectively, on circulating levels of sterols, markers of cholesterol biosynthesis and minerals, and on the development and progression of aortic lesions in apoE-deficient mice. To this end, mice were fed a western diet with either casein (200 g/kg; served as a control), conglutin γ from L. angustifolius (200 g/kg) or casein (200 g/kg) supplemented with phytate (5 g/kg) for 16 weeks. Here we found that conglutin γ but not phytate was capable of reducing the circulating concentration of cholesterol. Plasma levels of desmosterol and lathosterol as markers of the cholesterol synthesis were not affected, and 7-dehydrocholesterol was even higher in mice fed conglutin γ than in mice fed casein or casein + phytate. All mice developed pronounced aortic lesions, but histological characterization of plaque area and composition showed no differences between the three groups of mice. Conclusively, conglutin γ exerts cholesterol-lowering effects but appears to have no anti-atherosclerotic properties in the apoE-deficient mice. Phytate neither affected plasma cholesterol nor aortic lesion development.

BACKGROUND: Increased fibroblast growth factor 23 (FGF23), a bone-derived hormone involved in the regulation of phosphate and vitamin D metabolism, has been related to the development of cardiovascular disease (CVD) in chronic kidney disease patients and in the general population. However, what determines higher FGF23 levels is still unclear. Also, little is known about the influence of diet on FGF23. The aim of this study was therefore to identify demographic, clinical and dietary correlates of high FGF23 concentrations in the general population. METHODS: We performed a cross-sectional analysis within a randomly selected subcohort of the European Prospective Investigation into Cancer and Nutrition (EPIC)-Germany comprising 2134 middle-aged men and women. The Human FGF23 (C-Terminal) ELISA kit was used to measure FGF23 in citrate plasma. Dietary data were obtained at baseline via validated food frequency questionnaires including up to 148 food items. RESULTS: Multivariable adjusted logistic regression showed that men had a 66% lower and smokers a 64% higher probability of having higher FGF23 (≥ 90 RU/mL) levels compared, respectively, with women and nonsmokers. Each doubling in parathyroid hormone, creatinine, and C-reactive protein was related to higher FGF23. Among the dietary factors, each doubling in calcium and total energy intake was related, respectively, to a 1.75 and to a 4.41 fold increased probability of having higher FGF23. Finally, each doubling in the intake of iron was related to an 82% lower probability of having higher FGF23 levels. Results did not substantially change after exclusion of participants with lower kidney function. CONCLUSIONS: In middle-aged men and women traditional and non-traditional CVD risk factors were related to higher FGF23 concentrations. These findings may contribute to the understanding of the potential mechanisms linking increased FGF23 to increased CVD risk.

In vitro studies suggest that high vitamin E supplementation has prooxidative activity, but very few studies have investigated this effect in vivo. We investigated the effect of excess vitamin E on the antioxidative status of rat erythrocytes and indicators of hemolysis. Six groups of growing male Sprague-Dawley rats were fed purified diets with three different vitamin E doses [100, 1000 and 10,000 mg all-rac-alpha-tocopheryl acetate (TA)/kg diet] and two different dietary fats (salmon oil and lard) for 8 wk. The rats whose diet contained salmon oil and 10,000 mg TA/kg had lower activities of superoxide dismutase (P < 0.05), glutathione peroxidase (P < 0.05), catalase (P < 0.05) and glucose-6-phosphate dehydrogenase (P < 0.05) and a lower concentration of glutathione (P < 0.05) in the erythrocyte cytosol than rats whose diet contained 100 mg TA/kg. The concentration of free hemoglobin and the binding capacity of haptoglobin in plasma, both indicators of in vivo hemolysis, did not differ between rats fed the salmon oil diet with 100 or 10,000 mg TA/kg. In the rats whose diet contained lard, the activities of antioxidant enzymes in erythrocytes and indicators of in vivo hemolysis were independent of the dietary vitamin E concentration. The results of the study suggest that an excessive vitamin E intake, when combined with salmon oil in the diet, lowers the activities of antioxidant enzymes in erythrocytes without affecting in vivo hemolysis.

The synthesis of three types of phospholipid analogs by use of enzymes is described. The first group of compounds comprises 1,3-diacylglycerols modified at 2-position being regioisomers of natural glycero-phospholipids. According to Schneider et al. (J. Am. Oil Chem. Soc. 69 (1992), 955-960), glycerol was acylated with the vinyl esters of fatty acids by 1,3-selective lipase from Rhizomucor miehei. Modification of these regioisomerically pure 1,3-diacylglycerols in the 2-position by conventional chemical methods yielded 1,3-diacylglycero-2-phosphocholines or other amphiphilic compounds. such as 1,3-dilauroylglycero-2-phosphate or 1,3-dilauroylglycero-2-sulfate. The second group of newly synthesized compounds represent 1,2-dioleoyl-sn-glycero-3-phospholipids with N-heterocyclic head groups. They were obtained from 1,2-dioleoyl-sn-glycero-3-phosphocholine by transphosphatidylation with phospholipase D from cabbage or Streptomyces sp. in two-phase systems. These results prove that phospholipases D from both sources are able to transfer the phosphatidyl moiety even to secondary alcohols. Finally, it is demonstrated that phospholipase D is also appropriate to catalyze the transesterification of alkylphosphate esters, such as the conversion of octadecylphosphocholine into octadecylphosphoryl-N-(2-hydroxyethyl)-N-methylpiperidine. Selected compounds of the three classes of phospholipid analogs were used to study their effectory properties on phospholipase D. 1,3-Di-lauroylglycero-2-phosphocholine as well as alkylphosphate esters act as inhibitors of phospholipase D from cabbage, whereas the anionic amphiphiles 1,3-dilauroylglycero-2-phosphate and 1,3-dilauroylglycero-2-sulfate activate the enzyme similar to sodium dodecylsulfate.

Tamoxifen is the standard adjuvant endocrine therapy for estrogen-receptor positive premenopausal breast cancer patients. However, tamoxifen resistance is frequently observed under therapy. A tamoxifen resistant cell line has been generated from the estrogen receptor positive mamma carcinoma cell line MCF-7 and was analyzed for putative differences in the aldehyde defence system and accumulation of advanced glycation end products (AGE). In comparison to wt MCF-7 cells, these tamoxifen resistant cells were more sensitive to the dicarbonyl compounds glyoxal and methylglyoxal and displayed increased caspase activity, p38-MAPK- and IκBα-phosphorylation. However, mRNA accumulation of the aldehyde- and AGE-defence enzymes glyoxalase-1 and -2 (GLO1, GLO2) as well as fructosamine-3-kinase (FN3K) was not significantly altered. Tamoxifen resistant cells contained less free sulfhydryl-groups (glutathione) suggesting that the increased sensitivity towards the dicarbonyls was due to a higher sensitivity towards reactive oxygen species which are associated with dicarbonyl stress. To further analyse, if these data are of more general importance, key experiments were replicated with tamoxifen resistant MCF-7 cell lines from two independent sources. These cell lines were also more sensitive to aldehydes, especially glyoxal, but were different in their cellular signalling responses to the aldehydes. In conclusion, glyoxalases and other aldehyde defence enzymes might represent a promising target for the therapy of tamoxifen resistant breast cancers.

Phospholipase D from cabbage or Streptomyces chromofuscus catalyses the transesterification of alkylphosphate esters, which are potent antitumor agents. The exchange of choline in octadecylphosphosphocholine by N-(2-hydroxy-ethyl)-N-methylpiperidine with phospholipase D from cabbage is kinetically controlled and amounts to maximum 60% in buffer, 43% in buffer/n-hexane, and 82% in buffer/n-hexane/1-octanol.

Scope Epidemiologic data reveal associations between low serum concentrations of 25-hydroxyvitamin D (25(OH)D) and higher risk of falls and muscle weakness. Fetal stage is critical for the development of skeletal muscle, but little information is available on the impact of maternal vitamin D deficiency on muscles of offspring. Methods and results To investigate the morphology and transcriptome of gastrocnemius muscle in newborns in response to maternal vitamin D deficiency, 14 female rats were fed either a vitamin D3 deficient (0 IU/kg) or a vitamin D3 adequate diet (1000 IU/kg) 8 weeks prior to conception, during pregnancy, and lactation. Analysis of cholecalciferol, 25(OH)D3 and 1,25-dihydroxyvitamin D3 show that dams fed the vitamin D deficient diet and their newborns suffered from a relevant vitamin D deficiency. Muscle cells of vitamin D deficient newborns were smaller than those of vitamin D adequate newborns (p < 0.05). Muscle transcriptome of the newborns revealed 426 probe sets as differentially expressed (259 upregulated, 167 downregulated) in response to vitamin D deficiency (fold change ≥1.5, p < 0.05). The effected genes are involved in protein catabolism, cell differentiation and proliferation, muscle cell development, and cytoskeleton organization. Conclusion Maternal vitamin D deficiency has a major impact on morphology and gene expression profile of skeletal muscle in newborns.