TY - JOUR A1 - Danquah, Ina A1 - Dobrucky, C. Lydia A1 - Frank, Laura K. A1 - Henze, Andrea A1 - Amoako, Yaw A. A1 - Bedu-Addo, George A1 - Raila, Jens A1 - Schulze, Matthias Bernd A1 - Mockenhaupt, Frank P. A1 - Schweigert, Florian J. T1 - Vitamin A: potential misclassification of vitamin A status among patients with type 2 diabetes and hypertension in urban Ghana JF - The American journal of clinical nutrition : a publication of the American Society for Nutrition, Inc. N2 - Background: Sub-Saharan Africa is facing a double burden of malnutrition: vitamin A deficiency (VAD) prevails, whereas the nutrition-related chronic conditions type 2 diabetes (T2D) and hypertension are emerging. Serum retinol a VAD marker increases in kidney disease and decreases in inflammation, which can partly be attributed to alterations in the vitamin A transport proteins retinol-binding protein 4 (RBP4) and prealbumin. Kidney dysfunction and inflammation commonly accompany T2D and hypertension. Objective: Among urban Ghanaians, we investigated the associations of T2D and hypertension with serum retinol as well as the importance of kidney function and inflammation in this regard. Design: A hospital-based, case-control study in individuals for risk factors of T2D, hypertension, or both was conducted in Kumasi, Ghana (328 controls, 197 with T2D, 354 with hypertension, and 340 with T2D plus hypertension). In 1219 blood samples, serum retinol, RBP4, and prealbumin were measured. Urinary albumin and estimated glomerular filtration rate (eGFR) defined kidney function. C-reactive protein (CRP) >5 mg/L indicated inflammation. We identified associations of T2D and hypertension with retinol by linear regression and calculated the contribution of RBP4, prealbumin, urinary albumin, eGFR, and CRP to these associations as the percentages of the explained variance of retinol. Results: VAD (retinol <1.05 mu mol/L) was present in 10% of this predominantly female, middle-aged, overweight, and deprived population. Hypertension, but not T2D, was positively associated with retinol (beta: 0.12; 95% CI: 0.08, 0,17), adjusted for age, sex, socioeconomic factors, anthropometric measurements, and lifestyle. In addition to RBP4 (72%) and prealbumin (22%), the effect of increased retinol on individuals with hypertension was mainly attributed to impaired kidney function (eGFR: 30%; urinary albumin: 5%) but not to inflammation. Conclusions: In patients with hypertension, VAD might be underestimated because of increased serum retinol in the context of kidney dysfunction. Thus, the interpretation of serum retinol in sub-Saharan Africa should account for hypertension status. KW - hypertension KW - inflammation KW - kidney dysfunction KW - type 2 diabetes KW - vitamin A deficiency Y1 - 2015 U6 - https://doi.org/10.3945/ajcn.114.101345 SN - 0002-9165 SN - 1938-3207 VL - 102 IS - 1 SP - 207 EP - 214 PB - American Society for Nutrition, Inc. CY - Bethesda ER - TY - JOUR A1 - Henze, Andrea A1 - Raila, Jens A1 - Kempf, Caroline A1 - Reinke, Petra A1 - Sefrin, Anett A1 - Querfeld, Uwe A1 - Schweigert, Florian J. T1 - Vitamin A metabolism is changed in donors after living-kidney transplantation an observational study JF - Lipids in health and disease N2 - Background: The kidneys are essential for the metabolism of vitamin A (retinol) and its transport proteins retinol-binding protein 4 (RBP4) and transthyretin. Little is known about changes in serum concentration after living donor kidney transplantation (LDKT) as a consequence of unilateral nephrectomy; although an association of these parameters with the risk of cardiovascular diseases and insulin resistance has been suggested. Therefore we analyzed the concentration of retinol, RBP4, apoRBP4 and transthyretin in serum of 20 living-kidney donors and respective recipients at baseline as well as 6 weeks and 6 months after LDKT. Results: As a consequence of LDKT, the kidney function of recipients was improved while the kidney function of donors was moderately reduced within 6 weeks after LDKT. With regard to vitamin A metabolism, the recipients revealed higher levels of retinol, RBP4, transthyretin and apoRBP4 before LDKT in comparison to donors. After LDKT, the levels of all four parameters decreased in serum of the recipients, while retinol, RBP4 as well as apoRBP4 serum levels of donors increased and remained increased during the follow-up period of 6 months. Conclusion: LDKT is generally regarded as beneficial for allograft recipients and not particularly detrimental for the donors. However, it could be demonstrated in this study that a moderate reduction of kidney function by unilateral nephrectomy, resulted in an imbalance of components of vitamin A metabolism with a significant increase of retinol and RBP4 and apoRBP4 concentration in serum of donors. KW - Donors KW - glomerular filtration rate KW - kidney transplantation KW - retinol KW - retinol-binding protein 4 KW - transthyretin Y1 - 2011 U6 - https://doi.org/10.1186/1476-511X-10-231 SN - 1476-511X VL - 10 IS - 23 PB - BioMed Central CY - London ER - TY - GEN A1 - Henze, Andrea A1 - Raila, Jens A1 - Kempf, Caroline A1 - Reinke, Petra A1 - Sefrin, Anett A1 - Querfeld, Uwe A1 - Schweigert, Florian J. T1 - Vitamin A metabolism is changed in donors after living-kidney transplantation BT - an observational study N2 - Background The kidneys are essential for the metabolism of vitamin A (retinol) and its transport proteins retinol-binding protein 4 (RBP4) and transthyretin. Little is known about changes in serum concentration after living donor kidney transplantation (LDKT) as a consequence of unilateral nephrectomy; although an association of these parameters with the risk of cardiovascular diseases and insulin resistance has been suggested. Therefore we analyzed the concentration of retinol, RBP4, apoRBP4 and transthyretin in serum of 20 living-kidney donors and respective recipients at baseline as well as 6 weeks and 6 months after LDKT. Results As a consequence of LDKT, the kidney function of recipients was improved while the kidney function of donors was moderately reduced within 6 weeks after LDKT. With regard to vitamin A metabolism, the recipients revealed higher levels of retinol, RBP4, transthyretin and apoRBP4 before LDKT in comparison to donors. After LDKT, the levels of all four parameters decreased in serum of the recipients, while retinol, RBP4 as well as apoRBP4 serum levels of donors increased and remained increased during the follow-up period of 6 months. Conclusion LDKT is generally regarded as beneficial for allograft recipients and not particularly detrimental for the donors. However, it could be demonstrated in this study that a moderate reduction of kidney function by unilateral nephrectomy, resulted in an imbalance of components of vitamin A metabolism with a significant increase of retinol and RBP4 and apoRBP4 concentration in serum of donors. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 373 KW - Donors KW - glomerular filtration rate KW - kidney transplantation KW - retinol KW - retinol-binding protein 4 KW - transthyretin Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-400942 ER - TY - JOUR A1 - Henze, Andrea A1 - Espe, Katharina M. A1 - Wanner, Christoph A1 - Krane, Vera A1 - Raila, Jens A1 - Hocher, Berthold A1 - Schweigert, Florian J. A1 - Drechsler, Christiane T1 - Transthyretin predicts cardiovascular outcome in hemodialysis patients with type 2 diabetes JF - Diabetes care N2 - OBJECTIVE-BMI and albumin are commonly accepted parameters to recognize wasting in dialysis patients and are powerful predictors of morbidity and mortality. However, both parameters reveal limitations and may not cover the entire range of patients with wasting. The visceral protein transthyretin (TTR) may be helpful in overcoming the diagnostic and prognostic gap. Therefore, the aim of this study was to assess the association of TTR with morbidity and mortality in hemodialysis patients. RESEARCH DESIGN AND METHODS-The TTR concentration was determined in plasma samples of 1,177 hemodialysis patients with type 2 diabetes. Cox regression analyses were used to determine hazard ratios (HRs) for the risk of cardiovascular end points (CVEs) and mortality according to quartiles of TTR concentration for the total study cohort and the subgroups BMI >= 23 kg/m(2), albumin concentration >= 3.8 g/dL, and a combination of both. RESULTS-A low TTR concentration was associated with an increased risk for CVE for the total study cohort (HR 1.65 [95% CI 1.27-2.14]), patients with BMI >= 23 kg/m(2) (1.70 [1.22-2.37]), albumin >= 3.8 g/dL (1.68 [1.17-2.42]), and the combination of both (1.69 [1.13-2.53]). Additionally, a low TTR concentration predicted mortality for the total study cohort (1.79 [1.43-2.24]) and patients with BMI >= 23 kg/m(2) (1.46 [1.09-1.95]). CONCLUSIONS-The current study demonstrated that TTR is a useful predictor for cardiovascular outcome and mortality in diabetic hemodialysis patients. TTR was particularly useful in patients who were not identified to be at risk by BMI or albumin status. Y1 - 2012 U6 - https://doi.org/10.2337/dc12-0455 SN - 0149-5992 VL - 35 IS - 11 SP - 2365 EP - 2372 PB - American Diabetes Association CY - Alexandria ER - TY - JOUR A1 - Döll, Stefanie A1 - Djalali Farahani-Kofoet, Roxana A1 - Zrenner, Rita A1 - Henze, Andrea A1 - Witzel, Katja T1 - Tissue-specific signatures of metabolites and proteins in asparagus roots and exudates JF - Horticulture research N2 - Comprehensive untargeted and targeted analysis of root exudate composition has advanced our understanding of rhizosphere processes. However, little is known about exudate spatial distribution and regulation. We studied the specific metabolite signatures of asparagus root exudates, root outer (epidermis and exodermis), and root inner tissues (cortex and vasculature). The greatest differences were found between exudates and root tissues. In total, 263 non-redundant metabolites were identified as significantly differentially abundant between the three root fractions, with the majority being enriched in the root exudate and/or outer tissue and annotated as 'lipids and lipid-like molecules' or 'phenylpropanoids and polyketides'. Spatial distribution was verified for three selected compounds using MALDI-TOF mass spectrometry imaging. Tissue-specific proteome analysis related root tissue-specific metabolite distributions and rhizodeposition with underlying biosynthetic pathways and transport mechanisms. The proteomes of root outer and inner tissues were spatially very distinct, in agreement with the fundamental differences between their functions and structures. According to KEGG pathway analysis, the outer tissue proteome was characterized by a high abundance of proteins related to 'lipid metabolism', 'biosynthesis of other secondary metabolites' and 'transport and catabolism', reflecting its main functions of providing a hydrophobic barrier, secreting secondary metabolites, and mediating water and nutrient uptake. Proteins more abundant in the inner tissue related to 'transcription', 'translation' and 'folding, sorting and degradation', in accord with the high activity of cortical and vasculature cell layers in growth- and development-related processes. In summary, asparagus root fractions accumulate specific metabolites. This expands our knowledge of tissue-specific plant cell function. Y1 - 2021 U6 - https://doi.org/10.1038/s41438-021-00510-5 SN - 2052-7276 SN - 2662-6810 VL - 8 IS - 1 PB - Nanjing Agricultural Univ. CY - Nanjing ER - TY - JOUR A1 - Reeg, Sandra A1 - Jung, Tobias A1 - Castro, José Pedro A1 - Davies, Kelvin J. A. A1 - Henze, Andrea A1 - Grune, Tilman T1 - The molecular chaperone Hsp70 promotes the proteolytic removal of oxidatively damaged proteins by the proteasome JF - Free radical biology and medicine : the official journal of the Oxygen Society, a constituent member of the International Society for Free Radical Research N2 - One hallmark of aging is the accumulation of protein aggregates, promoted by the unfolding of oxidized proteins. Unraveling the mechanism by which oxidized proteins are degraded may provide a basis to delay the early onset of features, such as protein aggregate formation, that contribute to the aging phenotype. In order to prevent aggregation of oxidized proteins, cells recur to the 20S proteasome, an efficient turnover proteolysis complex. It has previously been shown that upon oxidative stress the 26S proteasome, another form, dissociates into the 20S form. A critical player implicated in its dissociation is the Heat Shock Protein 70 (Hsp70), which promotes an increase in free 20S proteasome and, therefore, an increased capability to degrade oxidized proteins. The aim of this study was to test whether or not Hsp70 is involved in cooperating with the 20S proteasome for a selective degradation of oxidatively damaged proteins. Our results demonstrate that Hsp70 expression is induced in HT22 cells as a result of mild oxidative stress conditions. Furthermore, Hsp70 prevents the accumulation of oxidized proteins and directly promotes their degradation by the 20S proteasome. In contrast the expression of the Heat shock cognate protein 70 (Hsc70) was not changed in recovery after oxidative stress and Hsc70 has no influence on the removal of oxidatively damaged proteins. We were able to demonstrate in HT22 cells, in brain homogenates from 129/SV mice and in vitro, that there is an increased interaction of Hsp70 with oxidized proteins, but also with the 20S proteasome, indicating a role of Hsp70 in mediating the interaction of oxidized proteins with the 20S proteasome. Thus, our data clearly implicate an involvement of Hsp70 oxidatively damaged protein degradation by the 20S proteasome. c) 2016 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). KW - Protein oxidation KW - Proteasome KW - Chaperone KW - HSP70 Y1 - 2016 U6 - https://doi.org/10.1016/j.freeradbiomed.2016.08.002 SN - 0891-5849 SN - 1873-4596 VL - 99 SP - 153 EP - 166 PB - Elsevier CY - New York ER - TY - JOUR A1 - Frede, Katja A1 - Henze, Andrea A1 - Khalil, Mahmoud A1 - Baldermann, Susanne A1 - Schweigert, Florian J. A1 - Rawel, Harshadrai Manilal T1 - Stability and cellular uptake of lutein-loaded emulsions JF - Journal of functional food N2 - The carotenoid lutein can improve human health. Since only a fraction is absorbed from food, lutein supplementation might be recommended. Emulsions could be good carrier systems to improve the bioavailability of lutein. Six different emulsifier compositions were used in this study to prepare lutein-loaded emulsions: beta-lactoglobulin, beta-lactoglobulin/lecithin, Biozate 1, Biozate 1/lecithin, Been 20 and Tween 20/lecithin. The droplet size, resistance to creaming, lutein stability, cytotoxicity and lutein uptake by HT29 cells were investigated. The whey protein beta-lactoglobulin, the whey protein hydrolysate Biozate 1 and the combination with lecithin brought the most promising results. The small droplet sizes and resistance to creaming were an indication of physical stable emulsions. Furthermore, these emulsifiers prevented oxidation of lutein. The choice of emulsifier had a strong impact on the uptake by HT29 cells. The highest lutein absorption was observed with the combination of Biozate 1 and lecithin. KW - Lutein KW - Emulsion KW - Whey protein KW - Stability KW - Bioavailability Y1 - 2014 U6 - https://doi.org/10.1016/j.jff.2014.03.011 SN - 1756-4646 VL - 8 SP - 118 EP - 127 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Münzner, Matthias A1 - Tuvia, Neta A1 - Deutschmann, Claudia A1 - Witte, Nicole A1 - Tolkachov, Alexander A1 - Valai, Atijeh A1 - Henze, Andrea A1 - Sander, Leif E. A1 - Raila, Jens A1 - Schupp, Michael T1 - Retinol-binding protein 4 and its membrane receptor STRA6 control adipogenesis by regulating cellular retinoid homeostasis and retinoic acid receptor alpha activity JF - Molecular and cellular biology N2 - Retinoids are vitamin A (retinol) derivatives and complex regulators of adipogenesis by activating specific nuclear receptors, including the retinoic acid receptor (RAR) and retinoid X receptor (RXR). Circulating retinol-binding protein 4 (RBP4) and its membrane receptor STRA6 coordinate cellular retinol uptake. It is unknown whether retinol levels and the activity of RAR and RXR in adipocyte precursors are linked via RBP4/STRA6. Here, we show that STRA6 is expressed in precursor cells and, dictated by the apo-and holo-RBP4 isoforms, mediates bidirectional retinol transport that controls RAR alpha activity and subsequent adipocyte differentiation. Mobilization of retinoid stores in mice by inducing RBP4 secretion from the liver activated RAR alpha signaling in the precursor cell containing the stromal-vascular fraction of adipose tissue. Retinol-loaded holo-RBP4 blocked adipocyte differentiation of cultured precursors by activating RAR alpha. Remarkably, retinol-free apo-RBP4 triggered retinol efflux that reduced cellular retinoids, RAR alpha activity, and target gene expression and enhanced adipogenesis synergistically with ectopic STRA6. Thus, STRA6 in adipocyte precursor cells links nuclear RAR alpha activity to the circulating RBP4 isoforms, whose ratio in obese mice was shifted toward limiting the adipogenic potential of their precursors. This novel cross talk identifies a retinoldependent metabolic function of RBP4 that may have important implications for the treatment of obesity. Y1 - 2013 U6 - https://doi.org/10.1128/MCB.00221-13 SN - 0270-7306 SN - 1098-5549 VL - 33 IS - 20 SP - 4068 EP - 4082 PB - American Society for Microbiology CY - Washington ER - TY - JOUR A1 - Bobbert, Thomas A1 - Raila, Jens A1 - Schwarz, Franziska A1 - Mai, Knut A1 - Henze, Andrea A1 - Pfeiffer, Andreas F. H. A1 - Schweigert, Florian J. A1 - Spranger, Joachim T1 - Relation between retinol, retinol-binding protein 4, transthyretin and carotid intima media thickness N2 - Objective: Retinol is transported in a complex with retinol-binding protein 4 (RBP4) and transthyretin (TTR) in the circulation. While retinol is associated with various cardiovascular risk factors, the relation between retinol, RBP4, TTR and carotid intima media thickness (IMT) has not been analysed yet. Methods: Retinol, RBP4 and TTR were measured in 96 individuals and their relation to mean and maximal IMT was determined. Results: Mean IMT correlated with RBP4 (r = 0.335, p < 0.001), retinol (r = -0.241, p = 0.043), RBP/TTR ratio (r = 0.254, p = 0.025) and retinol/RBP4 ratio (r = -0.549, p < 0.001). Adjustment for age, sex, BMI, blood pressure, HDL/total cholesterol ratio, triglyceride, diabetes and smoking revealed that the retinol/RBP4 ratio was strongly and independently associated with mean IMT. Similar results were found for maximal IMT, which included the measurement of plaques. Conclusion: The data support that the transport complex of vitamin A is associated with the IMT, an established parameter of atherosclerosis. Changes in RBP4 saturation with retinol may link renal dysfunction and insulin resistance to atherosclerosis. Y1 - 2010 UR - http://www.sciencedirect.com/science/journal/00219150 U6 - https://doi.org/10.1016/j.atherosclerosis.2010.07.063 SN - 0021-9150 ER - TY - GEN A1 - Henze, Andrea T1 - Proteinoxidation als Indikator des Alterungsphänotyps und Target einer individualisierten Ernährungsintervention (ProAID) T1 - Protein Oxidation as an Indicator of the Aging Phenotype and Target of an individualized Nutritional Intervention (ProAID) T2 - Ernährungs-Umschau : Forschung & Praxis N2 - Oxidative posttranslationale Modifikationen endogener Proteine werden v. a. durch reaktive Sauerstoff- und Stickstoffspezies (engl:. Reactive Oxygen Species, ROS, reactive nitrogen species, RNS) hervorgerufen und können sowohl reversibel (z. B. Disulfidbindungen) als auch irreversibel (z. B. Proteincarbonyle) erfolgen [1–3]. Lange wurde angenommen, dass oxidative posttranslationale Proteinmodifikationen (oxPTPM) nur von untergeordneter Bedeutung für den Metabolismus sind. Tatsächlich handelt es sich jedoch um einen physiologischen Prozess, der über die Modulation der Proteinstruktur auch die Proteinfunktion (z. B. Enzymaktivität, Stabilität) und somit zahlreiche Stoffwechselwege wie den Energiestoffwechsel, die Immunfunktion, die vaskuläre Funktion sowie Apoptose und Genexpression beeinflussen kann. Die Bildung von oxPTPM ist dabei hochreguliert und hängt u. a. von der Proteinstruktur, der Verfügbarkeit von ROS und RNS sowie dem lokalen Mikromilieu der Zelle ab [2, 4]. Y1 - 2018 SN - 0174-0008 VL - 65 IS - 10 SP - M566 EP - M567 PB - Umschau-Zeitschriftenverl. CY - Frankfurt, Main ER - TY - JOUR A1 - Schutkowski, Alexandra A1 - König, Bettina A1 - Kluge, Holger A1 - Hirche, Frank A1 - Henze, Andrea A1 - Schwerdtle, Tanja A1 - Lorkowski, Stefan A1 - Dawczynski, Christine A1 - Gabel, Alexander A1 - Grosse, Ivo A1 - Stangl, Gabriele I. T1 - Metabolic footprint and intestinal microbial changes in response to dietary proteins in a pig model JF - The journal of nutritional biochemistry N2 - 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. KW - Lupin KW - Beef KW - Casein KW - Pig KW - Biomarker KW - Microbiome Y1 - 2019 U6 - https://doi.org/10.1016/j.jnutbio.2019.02.004 SN - 0955-2863 SN - 1873-4847 VL - 67 SP - 149 EP - 160 PB - Elsevier CY - New York ER - TY - CHAP A1 - Espe, Katharina M. A1 - Raila, Jens A1 - Henze, Andrea A1 - Blouin, Katja A1 - Schneider, A. A1 - Schmiedeke, D. A1 - Krane, Vera A1 - Schweigert, Florian J. A1 - Hocher, Berthold A1 - Wanner, Christoph A1 - Drechsler, Christiane T1 - Low vitamin E plasma levels are associated with cerebrovascular events and mortality in hemodialysis patients T2 - Annals of nutrition & metabolism : journal of nutrition, metabolic diseases and dietetics ; an official journal of International Union of Nutritional Sciences (IUNS) Y1 - 2012 SN - 0250-6807 VL - 60 IS - 2 SP - 137 EP - 137 PB - Karger CY - Basel ER - TY - JOUR A1 - Espe, Katharina M. A1 - Raila, Jens A1 - Henze, Andrea A1 - Blouin, Katja A1 - Schneider, Andreas A1 - Schmiedeke, Daniel A1 - Krane, Vera A1 - Pilz, Stefan A1 - Schweigert, Florian J. A1 - Hocher, Berthold A1 - Wanner, Christoph A1 - Drechsler, Christiane T1 - Low plasma alpha-tocopherol concentrations and adverse clinical outcomes in diabetic hemodialysis patients JF - Clinical journal of the American Society of Nephrology N2 - Background and objectives Trials with the antioxidant vitamin E have failed to show benefit in the general population. Considering the different causes of death in ESRD, this study investigated the association between plasma concentrations of alpha-tocopherol and specific clinical outcomes in diabetic hemodialysis patients. Design, settings, participants, & measurements In 1046 diabetic hemodialysis patients (participants of the German Diabetes and Dialysis Study), alpha-tocopherol was measured in plasma by reversed-phase HPLC. By Cox regression analyses, hazard ratios were determined for prespecified end points according to baseline plasma alpha-tocopherol levels: sudden death (n=134), myocardial infarction (n=172), stroke (n=89), combined cardiovascular events (n=398), fatal infection (n=107), and all-cause mortality (n=508). Results Patients had a mean age of 66 8 years, and mean plasma alpha-tocopherol level was 22.8+/-9.6 mu mol/L. Levels of alpha-tocopherol were highly correlated to triglycerides (r=0.63, P<0.001). Patients in the lowest alpha-tocopherol quartile had (in unadjusted analyses) a 79% higher risk of stroke and a 31% higher risk of all-cause mortality compared with patients in the highest quartile. The associations were attenuated after adjustment for confounders (hazard ratio(stroke)=1.56, 95% confidence interval=0.75-3.25; hazard ratio(mortality)=1.22, 95% confidence interval=0.89-1.69, respectively). There was no association between alpha-tocopherol and myocardial infarction, sudden death, or infectious death. Conclusions Plasma alpha-tocopherol concentrations were not independently associated with cardiovascular outcomes, infectious deaths, or all-cause mortality in diabetic hemodialysis patients. The lack of association can partly be explained by a confounding influence of malnutrition, which should be considered in the planning of trials to reduce cardiovascular risk in dialysis patients. Y1 - 2013 U6 - https://doi.org/10.2215/CJN.04880511 SN - 1555-9041 VL - 8 IS - 3 SP - 452 EP - 458 PB - American Society of Nephrology CY - Washington ER - TY - JOUR A1 - Fedders, Ronja A1 - Muenzner, Matthias A1 - Weber, Pamela A1 - Sommerfeld, Manuela A1 - Knauer, Miriam A1 - Kedziora, Sarah A1 - Kast, Naomi A1 - Heidenreich, Steffi A1 - Raila, Jens A1 - Weger, Stefan A1 - Henze, Andrea A1 - Schupp, Michael T1 - Liver-secreted RBP4 does not impair glucose homeostasis in mice JF - The journal of biological chemistry N2 - Retinol-binding protein 4 (RBP4) is the major transport protein for retinol in blood. Recent evidence from genetic mouse models shows that circulating RBP4 derives exclusively from hepatocytes. Because RBP4 is elevated in obesity and associates with the development of glucose intolerance and insulin resistance, we tested whether a liver-specific overexpression of RBP4 in mice impairs glucose homeostasis. We used adeno-associated viruses (AAV) that contain a highly liver-specific promoter to drive expression of murine RBP4 in livers of adult mice. The resulting increase in serum RBP4 levels in these mice was comparable with elevated levels that were reported in obesity. Surprisingly, we found that increasing circulating RBP4 had no effect on glucose homeostasis. Also during a high-fat diet challenge, elevated levels of RBP4 in the circulation failed to aggravate the worsening of systemic parameters of glucose and energy homeostasis. These findings show that liver-secreted RBP4 does not impair glucose homeostasis. We conclude that a modest increase of its circulating levels in mice, as observed in the obese, insulin-resistant state, is unlikely to be a causative factor for impaired glucose homeostasis. KW - liver KW - retinoid-binding protein KW - glucose metabolism KW - insulin resistance KW - mouse KW - TTR Y1 - 2018 U6 - https://doi.org/10.1074/jbc.RA118.004294 SN - 1083-351X VL - 293 IS - 39 SP - 15269 EP - 15276 PB - American Society for Biochemistry and Molecular Biology CY - Bethesda ER - TY - JOUR A1 - Espe, Katharina M. A1 - Raila, Jens A1 - Henze, Andrea A1 - Krane, Vera A1 - Schweigert, Florian J. A1 - Hocher, Berthold A1 - Wanner, Christoph A1 - Drechsler, Christiane T1 - Impact of vitamin A on clinical outcomes in haemodialysis patients JF - Nephrology, dialysis, transplantation N2 - Background. Patients on maintenance haemodialysis treatment experience an excessive risk of cardiovascular disease and mortality. The vitamin A concentration is known to be higher in these patients compared to the general population where elevated vitamin A concentrations are associated with adverse outcome. The impact of vitamin A on morbidity and mortality in end-stage renal disease patients is controversial and is the topic of this study. Methods. We analysed plasma retinol and retinol-binding protein 4 (RBP4) in 1177 diabetic haemodialysis patients, who participated in the German Diabetes and Dialysis Study (median follow-up 4 years). By Cox regression analyses hazard ratios (HRs) were determined for pre-specified, adjudicated end points according to baseline concentrations. Results. Patients had a mean age of 66 +/- 8 years, mean retinol and RBP4 concentrations of 3.28 (0.71-7.44) and 4.02 (1.28-10.1) mu mol/L, respectively. Patients with retinol concentrations in the first quartile (<2.6 mu mol/L) had an almost 2-fold increased risk of all-cause mortality compared to patients of the fourth quartile [>3.9 mu mol/L; HR 1.81, 95% confidence interval (CI) 1.43-2.30]. There was a strong association between low retinol and the risk of sudden cardiac death (SCD, HR 2.22, 95% CI 1.41-3.50) and fatal infection (HR 2.19, 95% CI 1.26-3.82). Patients with RBP4 concentrations in the lowest quartile (<3.0 mu mol/L) were more likely to die of any cause (HR 1.43, 95% CI 1.14-1.80), experience SCD (HR 1.97, 95% CI 1.28-3.03) and cardiovascular events (HR 1.43, 95% CI 1.10-1.85). Conclusion. This large cohort study shows a strong association of low retinol and RBP4 concentrations with SCD and all-cause mortality in diabetic haemodialysis patients. KW - haemodialysis KW - mortality KW - retinol KW - retinol-binding protein 4 KW - sudden death Y1 - 2011 U6 - https://doi.org/10.1093/ndt/gfr171 SN - 0931-0509 VL - 26 IS - 12 SP - 4054 EP - U583 PB - Oxford Univ. Press CY - Oxford ER - TY - JOUR A1 - Henze, Andrea A1 - Aumer, Franziska A1 - Grabner, Arthur A1 - Raila, Jens A1 - Schweigert, Florian J. T1 - Genetic differences in the serum proteome of horses, donkeys and mules are detectable by protein profiling JF - The British journal of nutrition : an international journal devoted to the science of human and animal nutrition N2 - Although horses and donkeys belong to the same genus, their genetic characteristics probably result in specific proteomes and post-translational modifications (PTM) of proteins. Since PTM can alter protein properties, specific PTM may contribute to species-specific characteristics. Therefore, the aim of the present study was to analyse differences in serum protein profiles of horses and donkeys as well as mules, which combine the genetic backgrounds of both species. Additionally, changes in PTM of the protein transthyretin (TTR) were analysed. Serum protein profiles of each species (five animals per species) were determined using strong anion exchanger ProteinChips (R) (Bio-Rad, Munich, Germany) in combination with surface-enhanced laser desorption ionisation-time of flight MS. The PTM of TTR were analysed subsequently by immunoprecipitation in combination with matrix-assisted laser desorption ionisation-time of flight MS. Protein profiling revealed species-specific differences in the proteome, with some protein peaks present in all three species as well as protein peaks that were unique for donkeys and mules, horses and mules or for horses alone. The molecular weight of TTR of horses and donkeys differed by 30Da, and both species revealed several modified forms of TTR besides the native form. The mass spectra of mules represented a merging of TTR spectra of horses and donkeys. In summary, the present study indicated that there are substantial differences in the proteome of horses and donkeys. Additionally, the results probably indicate that the proteome of mules reveal a higher similarity to donkeys than to horses. KW - Mass spectrometry KW - Post-translational modifications KW - Proteome KW - Species differences Y1 - 2011 U6 - https://doi.org/10.1017/S0007114511000845 SN - 0007-1145 VL - 106 SP - S170 EP - S173 PB - Cambridge Univ. Press CY - Cambridge ER - TY - GEN A1 - Henze, Andrea A1 - Aumer, Franziska A1 - Grabner, Arthur A1 - Raila, Jens A1 - Schweigert, Florian J. T1 - Genetic differences in the serum proteome of horses, donkeys and mules are detectable by protein profiling T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Although horses and donkeys belong to the same genus, their genetic characteristics probably result in specific proteomes and post-translational modifications (PTM) of proteins. Since PTM can alter protein properties, specific PTM may contribute to species-specific characteristics. Therefore, the aim of the present study was to analyse differences in serum protein profiles of horses and donkeys as well as mules, which combine the genetic backgrounds of both species. Additionally, changes in PTM of the protein transthyretin (TTR) were analysed. Serum protein profiles of each species (five animals per species) were determined using strong anion exchanger ProteinChips (R) (Bio-Rad, Munich, Germany) in combination with surface-enhanced laser desorption ionisation-time of flight MS. The PTM of TTR were analysed subsequently by immunoprecipitation in combination with matrix-assisted laser desorption ionisation-time of flight MS. Protein profiling revealed species-specific differences in the proteome, with some protein peaks present in all three species as well as protein peaks that were unique for donkeys and mules, horses and mules or for horses alone. The molecular weight of TTR of horses and donkeys differed by 30Da, and both species revealed several modified forms of TTR besides the native form. The mass spectra of mules represented a merging of TTR spectra of horses and donkeys. In summary, the present study indicated that there are substantial differences in the proteome of horses and donkeys. Additionally, the results probably indicate that the proteome of mules reveal a higher similarity to donkeys than to horses. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 567 KW - mass spectrometry KW - post-translational modifications KW - proteome KW - species differences Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-412886 SN - 1866-8372 IS - 567 ER - TY - JOUR A1 - Fruscalzo, Arrigo A1 - Frommer, Julia-Marie A1 - Londero, Ambrogio P. A1 - Henze, Andrea A1 - Schweigert, Florian J. A1 - Nofer, Jerzy-Roch A1 - Steinhard, Johannes A1 - Klockenbusch, Walter A1 - Schmitz, Ralf A1 - Raila, Jens T1 - First trimester TTR-RBP4-ROH complex and angiogenic factors in the prediction of small for gestational age infant’s outcome JF - Archives of gynecology and obstetrics N2 - To study the role of the TTR-RBP4-ROH complex components (transthyretin, serum retinol binding protein, retinol) and of angiogenic factors PlGF (placental growth factor) and sFlt-1 (soluble fms-like tyrosine kinase-1) in pregnancies complicated by small for gestational age infants (SGA). Case control study conducted on maternal serum collected between 11 + 0 to 13 + 6 weeks of gestation. TTR, RBP4, ROH, PlGF and sFlt-1 were measured in SGA patients (birth weight < 10%) who delivered at term (n = 37) and before 37 weeks of gestation (n = 17) and in a matched control group with uneventful pregnancies (n = 37). We found decreased RBP4 in SGA patients that delivered fetuses < 3% and in fetuses delivered after the 37 weeks of gestation compared to controls [1.50 (95% CI 1.40-1.75) vs 1.62 (95% CI 1.47-1.98), p < 0.05]. Further, we found lower PlGF and sFlt-1 concentrations in SGA that delivered before 37 weeks of gestation compared to controls (respectively, PIGF and sFlt-1: 39.7 pg/ml (95% CI 32.3-66.3) vs 62.9 pg/ml (95% CI 45.2-78.4) and 906 pg/ml (95% CI 727-1626) vs 1610 pg/ml (95% CI 1088-212), p < 0.05). First trimester maternal serum RBP4 and angiogenic factors PlGF and sFlt-1 can differently predict the timing of delivery of pregnancies complicated by SGA fetuses. KW - Low birth weight KW - Small for gestational age KW - Pregnancy KW - First trimester KW - Marker KW - RBP4 KW - TTR KW - Retinol KW - Vitamin A KW - sFlt-1 KW - PlGF Y1 - 2017 U6 - https://doi.org/10.1007/s00404-017-4338-4 SN - 0932-0067 SN - 1432-0711 VL - 295 SP - 1157 EP - 1165 PB - Springer CY - Heidelberg ER - TY - JOUR A1 - Fruscalzo, Arrigo A1 - Londero, Ambrogio P. A1 - Driul, Lorenza A1 - Henze, Andrea A1 - Tonutti, Laura A1 - Ceraudo, Maria A1 - Zanotti, Giuseppe A1 - Berni, Rodolfo A1 - Schweigert, Florian J. A1 - Raila, Jens T1 - First trimester concentrations of the TTR-RBP4-retinol complex components as early markers of insulin-treated gestational diabetes mellitus JF - Clinical chemistry and laboratory medicine : journal of the Forum of the European Societies of Clinical Chemistry - the European Branch of the International Federation of Clinical Chemistry and Laboratory Medicine N2 - Background: The objective of the study was to investigate the relationship between first trimester maternal serum levels of the TTR-RBP4-ROH complex components and the later insurgence of an altered glucose metabolism during pregnancy. Methods: Retrospective case control study including 96 patients between the 12th and 14th week of gestation, 32 that developed gestational diabetes mellitus (GDM), respectively, 21 non-insulin-treated (dGDM) and 11 insulin-treated (iGDM), 20 large for gestational age fetuses (LGA) without GDM and 44 patients with normal outcome as control. Serum concentrations of RBP4 and TTR were assessed by ELISA; serum concentration of ROH by reverse-phase high performance liquid chromatography (rpHPLC). The molecular heterogeneity of TTR and RBP4 was analyzed after immunoprecipitation by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Results: iGDM patients were characterized by reduced TTR, RBP4 and ROH compared to controls (respectively, iGDM vs. controls, mean +/- SD: TTR 3.96 +/- 0.89 mu mol/L vs. 4.68 +/- 1.21 mu mol/L, RBP4 1.13 +/- 0.25 mu mol/L vs. 1.33 +/- 0.38 mu mol/L and ROH 1.33 +/- 0.17 mu mol/L vs. 1.62 +/- 0.29 mu mol/L, p < 0.05). TTR containing Gly10 in place of Cys10 was lower in the iGDM group (p < 0.05) compared to controls. In the final logistic regression model ROH significantly predicted the diagnosis of iGDM (OR 0.93, 95% CI 0.87-0.98, p < 0.05). Conclusions: First trimester maternal serum ROH, RBP4 and TTR represent potential biomarkers associated with the development of iGDM. KW - first trimester KW - gestational diabetes mellitus (GDM) KW - insulin KW - large for gestational age fetus (LGA) KW - protein microheterogeneity KW - retinol (ROH) KW - serum retinol binding protein (RBP4) KW - transthyretin (TTR) Y1 - 2015 U6 - https://doi.org/10.1515/cclm-2014-0929 SN - 1434-6621 SN - 1437-4331 VL - 53 IS - 10 SP - 1643 EP - 1651 PB - De Gruyter CY - Berlin ER - TY - JOUR A1 - Frey, Simone K. A1 - Spranger, Joachim A1 - Henze, Andrea A1 - Pfeiffer, Andreas F. H. A1 - Schweigert, Florian J. A1 - Raila, Jens T1 - Factors that influence retinol-binding protein 4-transthyretin interaction are not altered in overweight subjects and overweight subjects with type 2 diabetes mellitus N2 - Retinol-binding protein 4 (RBP4) is an adipokine bound in plasma to transthyretin (TTR), which prevents its glomerular filtration and subsequent catabolism in the kidney. Alterations of this interaction have been Suggested to be implicated in the elevation of RBP4 that are thought to contribute to the development Of insulin resistance associated with obesity and type 2 diabetes mellitus (T2DM). However, the factors linking RBP4 to TTR in humans are not clear. Therefore, this Study evaluated parameters influencing the RBP4-TTR interaction and their relation to obesity and T2DM. The RBP4 and TTR levels were quantified in plasma of 16 lean controls, 28 overweight controls, and 14 overweight T2DM patients by enzyme-linked immunosorbent assay. Transthyretin isoforms involved in RBP4 binding were determined by linear matrix-assisted laser desorption/ionization-time of flight-mass spectrometry after RBP4 coimmunoprecipitation. Holo-RBP4 (retinol-bound) and apo-RBP4 (retinol-free) were assessed by immunoblotting using nondenaturating polyacrylamide gel electrophoresis. Plasma levels of both RBP4 and TTR did not differ among the groups of lean controls, overweight controls, and overweight T2DM subjects. Using RBP4 immunoprecipitation, 4 mass signals were observed for TTR representing native, S-cysteinylated, S-cysteinglycinylated, and S-glutathionylated TTR. No differences in peak intensity of TTR isoforms were observed among the groups. Moreover, no differences in the ratio of holo- and apo-RBP4 were evident. The results suggest that circulating RBP4 and TTR were not affected by human obesity or T2DM, which might be attributed to the absence of alterations of TTR isoforms and the ratio of holo- and apo-RBP4 that might modify the TTR-RBP4 interaction. Y1 - 2009 UR - http://www.sciencedirect.com/science/journal/00260495 U6 - https://doi.org/10.1016/j.metabol.2009.05.003 SN - 0026-0495 ER -