TY - JOUR A1 - Putra, Sulistyo Emantoko Dwi A1 - Neuber, Corinna A1 - Reichetzeder, Christoph A1 - Hocher, Berthold A1 - Kleuser, Burkhard T1 - Analysis of genomic DNA methylation levels in human placenta using liquid Chromatography-Electrospray ionization tandem mass spectrometry JF - Cellular physiology and biochemistry : international journal of experimental cellular physiology, biochemistry and pharmacology N2 - Background: DNA-methylation is a common epigenetic tool which plays a crucial role in gene regulation and is essential for cell differentiation and embryonic development. The placenta is an important organ where gene activity can be regulated by epigenetic DNA modifications, including DNA methylation. This is of interest as, the placenta is the interface between the fetus and its environment, the mother. Exposure to environmental toxins and nutrition during pregnancy may alter DNA methylation of the placenta and subsequently placental function and as a result the phenotype of the offspring. The aim of this study was to develop a reliable method to quantify DNA methylation in large clinical studies. This will be a tool to analyze the degree of DNA methylation in the human placenta in relationship to clinical readouts. Methods: Liquid chromatography-electrospray ionization/multi-stage mass spectrometry (LC-ESI/MS/MS) technique was used for the quantification of the 5dmC/dG ratio in placentas from 248 healthy pregnancies. We were able to demonstrate that this method is a reliable and stable way to determine global placental DNA methylation in large clinical trials. Results/Conclusion: The degree of placental DNA methylation seen in our pilot study varies substantially from 2% to 5%. The clinical implications of this variation need to be demonstrated in adequately powered large studies. KW - Pregnancy KW - Placenta KW - Methylation KW - Global KW - LC-MS/MS KW - Fetal programming KW - Clinical Y1 - 2014 U6 - https://doi.org/10.1159/000358666 SN - 1015-8987 SN - 1421-9778 VL - 33 IS - 4 SP - 945 EP - 952 PB - Karger CY - Basel ER - TY - GEN A1 - Hocher, Berthold A1 - Reichetzeder, Christoph A1 - Dwi Putra, Sulistyo Emantoko A1 - Slowinski, Torsten A1 - Neuber, Corinna A1 - Kleuser, Burkhard A1 - Pfab, Thiemo T1 - Increased global placental DNA methylation levels are associated with gestational diabetes N2 - Background: Gestational diabetes mellitus (GDM) is associated with adverse pregnancy outcomes. It is known that GDM is associated with an altered placental function and changes in placental gene regulation. More recent studies demonstrated an involvement of epigenetic mechanisms. So far, the focus regarding placental epigenetic changes in GDM was set on gene-specific DNA methylation analyses. Studies that robustly investigated placental global DNA methylation are lacking. However, several studies showed that tissue-specific alterations in global DNA methylation are independently associated with type 2 diabetes. Thus, the aim of this study was to characterize global placental DNA methylation by robustly measuring placental DNA 5-methylcytosine (5mC) content and to examine whether differences in placental global DNA methylation are associated with GDM. Methods: Global DNA methylation was quantified by the current gold standard method, LC-MS/MS. In total, 1030 placental samples were analyzed in this single-center birth cohort study. Results: Mothers with GDM displayed a significantly increased global placental DNA methylation (3.22 ± 0.63 vs. 3.00 ± 0.46 %; p = 0.013; ±SD). Bivariate logistic regression showed a highly significant positive correlation between global placental DNA methylation and the presence of GDM (p = 0.0009). Quintile stratification according to placental DNA 5mC levels revealed that the frequency of GDM was evenly distributed in quintiles 1–4 (2.9–5.3 %), whereas the frequency in the fifth quintile was significantly higher (10.7 %; p = 0.003). Bivariate logistic models adjusted for maternal age, BMI, ethnicity, recurrent miscarriages, and familiar diabetes predisposition clearly demonstrated an independent association between global placental DNA hypermethylation and GDM. Furthermore, an ANCOVA model considering known predictors of DNA methylation substantiated an independent association between GDM and placental DNA methylation. Conclusions: This is the first study that employed a robust quantitative assessment of placental global DNA methylation in over a thousand placental samples. The study provides large scale evidence that placental global DNA hypermethylation is associated with GDM, independent of established risk factors. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 370 KW - Placenta KW - Gestational diabetes KW - Insulin resistance KW - LC-MS/MS KW - Global DNA methylation KW - Epigenetics KW - Hypermethylation Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-400914 ER - TY - JOUR A1 - Reichetzeder, Christoph A1 - Putra, S. E. Dwi A1 - Pfab, T. A1 - Slowinski, T. A1 - Neuber, Corinna A1 - Kleuser, Burkhard A1 - Hocher, Berthold T1 - Increased global placental DNA methylation levels are associated with gestational diabetes JF - Clinical epigenetics N2 - Background: Gestational diabetes mellitus (GDM) is associated with adverse pregnancy outcomes. It is known that GDM is associated with an altered placental function and changes in placental gene regulation. More recent studies demonstrated an involvement of epigenetic mechanisms. So far, the focus regarding placental epigenetic changes in GDM was set on gene-specific DNA methylation analyses. Studies that robustly investigated placental global DNA methylation are lacking. However, several studies showed that tissue-specific alterations in global DNA methylation are independently associated with type 2 diabetes. Thus, the aim of this study was to characterize global placental DNA methylation by robustly measuring placental DNA 5-methylcytosine (5mC) content and to examine whether differences in placental global DNA methylation are associated with GDM. Methods: Global DNA methylation was quantified by the current gold standard method, LC-MS/MS. In total, 1030 placental samples were analyzed in this single-center birth cohort study. Results: Mothers with GDM displayed a significantly increased global placental DNA methylation (3.22 +/- 0.63 vs. 3.00 +/- 0.46 %; p = 0.013; +/- SD). Bivariate logistic regression showed a highly significant positive correlation between global placental DNA methylation and the presence of GDM (p = 0.0009). Quintile stratification according to placental DNA 5mC levels revealed that the frequency of GDM was evenly distributed in quintiles 1-4 (2.9-5.3 %), whereas the frequency in the fifth quintile was significantly higher (10.7 %; p = 0.003). Bivariate logistic models adjusted for maternal age, BMI, ethnicity, recurrent miscarriages, and familiar diabetes predisposition clearly demonstrated an independent association between global placental DNA hypermethylation and GDM. Furthermore, an ANCOVA model considering known predictors of DNA methylation substantiated an independent association between GDM and placental DNA methylation. Conclusions: This is the first study that employed a robust quantitative assessment of placental global DNA methylation in over a thousand placental samples. The study provides large scale evidence that placental global DNA hypermethylation is associated with GDM, independent of established risk factors. KW - Placenta KW - Gestational diabetes KW - Insulin resistance KW - LC-MS/MS KW - Global DNA methylation KW - Epigenetics KW - Hypermethylation Y1 - 2016 U6 - https://doi.org/10.1186/s13148-016-0247-9 SN - 1868-7083 VL - 8 PB - BioMed Central CY - London ER - TY - JOUR A1 - Reichetzeder, Christoph T1 - Overweight and obesity in pregnancy BT - their impact on epigenetics JF - European journal of clinical nutrition N2 - Over the last few decades, the prevalence of obesity has risen to epidemic proportions worldwide. Consequently, the number of obesity in pregnancy has risen drastically. Gestational overweight and obesity are associated with impaired outcomes for mother and child. Furthermore, studies show that maternal obesity can lead to long-term consequences in the offspring, increasing the risk for obesity and cardiometabolic disease in later life. In addition to genetic mechanisms, mounting evidence demonstrates the induction of epigenetic alterations by maternal obesity, which can affect the offspring's phenotype, thereby influencing the later risk of obesity and cardiometabolic disease. Clear evidence in this regard comes from various animal models of maternal obesity. Evidence derived from clinical studies remains limited. The current article gives an overview of pathophysiological changes associated with maternal obesity and their consequences on placental structure and function. Furthermore, a short excurse is given on epigenetic mechanisms and emerging data regarding a putative interaction between metabolism and epigenetics. Finally, a summary of important findings of animal and clinical studies investigating maternal obesity-related epigenetic effects is presented also addressing current limitations of clinical studies. Y1 - 2021 U6 - https://doi.org/10.1038/s41430-021-00905-6 SN - 0954-3007 SN - 1476-5640 VL - 75 IS - 12 SP - 1710 EP - 1722 PB - Springer Nature CY - London ER - TY - JOUR A1 - Hocher, Berthold A1 - Haumann, Hannah A1 - Rahnenführer, Jan A1 - Reichetzeder, Christoph A1 - Kalk, Philipp A1 - Pfab, Thiemo A1 - Tsuprykov, Oleg A1 - Winter, Stefan A1 - Hofmann, Ute A1 - Li, Jian A1 - Püschel, Gerhard Paul A1 - Lang, Florian A1 - Schuppan, Detlef A1 - Schwab, Matthias A1 - Schaeffeler, Elke T1 - Maternal eNOS deficiency determines a fatty liver phenotype of the offspring in a sex dependent manner JF - Epigenetics : the official journal of the DNA Methylation Society N2 - Maternal environmental factors can impact on the phenotype of the offspring via the induction of epigenetic adaptive mechanisms. The advanced fetal programming hypothesis proposes that maternal genetic variants may influence the offspring's phenotype indirectly via epigenetic modification, despite the absence of a primary genetic defect. To test this hypothesis, heterozygous female eNOS knockout mice and wild type mice were bred with male wild type mice. We then assessed the impact of maternal eNOS deficiency on the liver phenotype of wild type offspring. Birth weight of male wild type offspring born to female heterozygous eNOS knockout mice was reduced compared to offspring of wild type mice. Moreover, the offspring displayed a sex specific liver phenotype, with an increased liver weight, due to steatosis. This was accompanied by sex specific differences in expression and DNA methylation of distinct genes. Liver global DNA methylation was significantly enhanced in both male and female offspring. Also, hepatic parameters of carbohydrate metabolism were reduced in male and female offspring. In addition, male mice displayed reductions in various amino acids in the liver. Maternal genetic alterations, such as partial deletion of the eNOS gene, can affect liver metabolism of wild type offspring without transmission of the intrinsic defect. This occurs in a sex specific way, with more detrimental effects in females. This finding demonstrates that a maternal genetic defect can epigenetically alter the phenotype of the offspring, without inheritance of the defect itself. Importantly, these acquired epigenetic phenotypic changes can persist into adulthood. KW - Epigenetics KW - eNOS KW - Fetal programming KW - fatty liver KW - metabolism Y1 - 2016 U6 - https://doi.org/10.1080/15592294.2016.1184800 SN - 1559-2294 SN - 1559-2308 VL - 11 SP - 539 EP - 552 PB - Routledge, Taylor & Francis Group CY - Philadelphia ER - TY - GEN A1 - de Pinho Tavares Leal, Pedro Ernesto A1 - da Silva, Alexandre Alves A1 - Rocha-Gomes, Arthur A1 - Riul, Tania Regina A1 - Cunha, Rennan Augusto A1 - Reichetzeder, Christoph A1 - Villela, Daniel Campos T1 - High-Salt Diet in the Pre- and Postweaning Periods Leads to Amygdala Oxidative Stress and Changes in Locomotion and Anxiety-Like Behaviors of Male Wistar Rats T2 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - High-salt (HS) diets have recently been linked to oxidative stress in the brain, a fact that may be a precursor to behavioral changes, such as those involving anxiety-like behavior. However, to the best of our knowledge, no study has evaluated the amygdala redox status after consuming a HS diet in the pre- or postweaning periods. This study aimed to evaluate the amygdala redox status and anxiety-like behaviors in adulthood, after inclusion of HS diet in two periods: preconception, gestation, and lactation (preweaning); and only after weaning (postweaning). Initially, 18 females and 9 male Wistar rats received a standard (n = 9 females and 4 males) or a HS diet (n = 9 females and 5 males) for 120 days. After mating, females continued to receive the aforementioned diets during gestation and lactation. Weaning occurred at 21-day-old Wistar rats and the male offspring were subdivided: control-control (C-C)—offspring of standard diet fed dams who received a standard diet after weaning (n = 9–11), control-HS (C-HS)—offspring of standard diet fed dams who received a HS diet after weaning (n = 9–11), HS-C—offspring of HS diet fed dams who received a standard diet after weaning (n = 9–11), and HS-HS—offspring of HS diet fed dams who received a HS diet after weaning (n = 9–11). At adulthood, the male offspring performed the elevated plus maze and open field tests. At 152-day-old Wistar rats, the offspring were euthanized and the amygdala was removed for redox state analysis. The HS-HS group showed higher locomotion and rearing frequency in the open field test. These results indicate that this group developed hyperactivity. The C-HS group had a higher ratio of entries and time spent in the open arms of the elevated plus maze test in addition to a higher head-dipping frequency. These results suggest less anxiety-like behaviors. In the analysis of the redox state, less activity of antioxidant enzymes and higher levels of the thiobarbituric acid reactive substances (TBARS) in the amygdala were shown in the amygdala of animals that received a high-salt diet regardless of the period (pre- or postweaning). In conclusion, the high-salt diet promoted hyperactivity when administered in the pre- and postweaning periods. In animals that received only in the postweaning period, the addition of salt induced a reduction in anxiety-like behaviors. Also, regardless of the period, salt provided amygdala oxidative stress, which may be linked to the observed behaviors. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1253 KW - high-sodium KW - open-field KW - elevated plus-maze KW - pre-natal KW - post-natal KW - redox state Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-557432 SN - 1866-8372 SP - 1 EP - 12 PB - Universitätsverlag Potsdam CY - Potsdam ER - TY - JOUR A1 - Hocher, Berthold A1 - Oberthür, Dominik A1 - Slowinski, Torsten A1 - Querfeld, Uwe A1 - Schäfer, Franz A1 - Doyon, Anke A1 - Tepel, Martin A1 - Roth, Heinz J. A1 - Grön, Hans J. A1 - Reichetzeder, Christoph A1 - Betzel, Christian A1 - Armbruster, Franz Paul T1 - Modeling of Oxidized PTH (oxPTH) and Non-oxidized PTH (n-oxPTH) Receptor Binding and Relationship of Oxidized to Non-Oxidized PTH in Children with Chronic Renal Failure, Adult Patients on Hemodialysis and Kidney Transplant Recipients JF - Kidney & blood pressure research : official organ of the Gesellschaft für Nephrologie N2 - Background: The biological properties of oxidized and non-oxidized PTH are substantially different. Oxidized PTH (oxPTH) loses its PTH receptor-stimulating properties, whereas non-oxidized PTH (n-oxPTH) is a full agonist of the receptor. This was described in more than 20 well published studies in the 1970(s) and 80(s). However, PTH oxidation has been ignored during the development of PTH assays for clinical use so far. Even the nowadays used third generation assay systems do not consider oxidation of PTH. We recently developed an assay to differentiate between oxPTH and n-oxPTH. In the current study we established normal values for this assay system. Furthermore, we compare the ratio of oxPTH to n-oxPTH in different population with chronic renal failure: 620 children with renal failure stage 2-4 of the 4C study, 342 adult patients on dialysis, and 602 kidney transplant recipients. In addition, we performed modeling of the interaction of either oxPTH or n-oxPTH with the PTH receptor using biophysical structure approaches. Results: The children had the highest mean as well as maximum n-oxPTH concentrations as compared to adult patients (both patients on dialysis as well as kidney transplant recipients). The relationship between oxPTH and n-oxPTH of individual patients varied substantially in all three populations with renal impairment. The analysis of n-oxPTH in 89 healthy control subjects revealed that n-oxPTH concentrations in patient with renal failure were higher as compared to healthy adult controls (2.25-fold in children with renal failure, 1.53-fold in adult patients on dialysis, and 1.56-fold in kidney transplant recipients, respectively). Computer assisted biophysical structure modeling demonstrated, however, minor sterical- and/or electrostatic changes in oxPTH and n-oxPTH. This indicated that PTH oxidation may induce refolding of PTH and hence alters PTH-PTH receptor interaction via oxidation induced three-dimensional structure alteration of PTH. Conclusion: A huge proportion of circulating PTH measured by current state-of-the-art assay systems is oxidized and thus not biologically active. The relationship between oxPTH and n-oxPTH of individual patients varied substantially. Non-oxidized PTH concentrations are 1.5 - 2.25 fold higher in patients with renal failure as compared to health controls. Measurements of n-oxPTH may reflect the hormone status more precise. The iPTH measures describes most likely oxidative stress in patients with renal failure rather than the PTH hormone status. This, however, needs to be demonstrated in further clinical studies. KW - n-oxPTH KW - Chronic Renal Failure KW - Kidney Transplantation KW - Hemodialysis KW - Oxidation KW - PTH KW - Chronic Renal Failure in Children Y1 - 2013 U6 - https://doi.org/10.1159/000350149 SN - 1420-4096 SN - 1423-0143 VL - 37 IS - 4-5 SP - 240 EP - 251 PB - Karger CY - Basel ER - TY - JOUR A1 - Feger, Martina A1 - Fajol, Abul A1 - Lebedeva, Aleksandra A1 - Meissner, Adrian A1 - Michael, Diana A1 - Völkl, Jakob A1 - Alesutan, Ioana A1 - Schleicher, Erwin A1 - Reichetzeder, Christoph A1 - Hocher, Berthold A1 - Qadri, Syed M. A1 - Lang, Florian T1 - Effect of Carbon Monoxide Donor CORM-2 on Vitamin D-3 Metabolism JF - Kidney & blood pressure research : official organ of the Gesellschaft für Nephrologie N2 - Background/Aims: Carbon monoxide (CO) interferes with cytochrome-dependent cellular functions and acts as gaseous transmitter. CO is released from CO-releasing molecules (CORM) including tricarbonyl-dichlororuthenium (II) dimer (CORM-2), molecules considered for the treatment of several disorders including vascular dysfunction, inflammation, tissue ischemia and organ rejection. Cytochrome P450-sensitive function include formation of 1,25-dihydroxyvitamin D-3 (1,25(OH)(2)D-3) by renal 25-hydroxyvitamin D-3 1-alpha-hydroxylase (Cyp27b1). The enzyme is regulated by PTH, FGF23 and klotho. 1,25(OH)(2)D-3 regulates Ca2+ and phosphate transport as well as klotho expression. The present study explored, whether CORM-2 influences 1,25(OH)(2)D-3 formation and klotho expression. Methods: Mice were treated with intravenous CORM-2 (20 mg/kg body weight). Plasma 1,25(OH)(2)D-3 and FGF23 concentrations were determined by ELISA, phosphate, calcium and creatinine concentrations by colorimetric methods, transcript levels by quantitative RT-PCR and protein expression by western blotting. Fgf23 mRNA transcript levels were further determined in rat osteosarcoma UMR106 cells without or with prior treatment for 24 hours with 20 mu M CORM-2. Results: CORM-2 injection within 24 hours significantly increased FGF23 plasma levels and decreased 1,25(OH)(2)D-3 plasma levels, renal Cyp27b1 gene expression as well as renal klotho protein abundance and transcript levels. Moreover, treatment of UMR106 cells with CORM-2 significantly increased Fgf23 transcript levels. Conclusion: CO-releasing molecule CORM-2 enhances FGF23 expression and release and decreases klotho expression and 1,25(OH)(2)D-3 synthesis. KW - CORM-2 KW - 1,25-Dihydroxyvitamin D-3 KW - Klotho KW - FGF23 KW - Phosphate KW - Calcium Y1 - 2013 U6 - https://doi.org/10.1159/000355730 SN - 1420-4096 SN - 1423-0143 VL - 37 IS - 4-5 SP - 496 EP - 505 PB - Karger CY - Basel ER - TY - INPR A1 - Hocher, Berthold A1 - Reichetzeder, Christoph T1 - Vitamin D and cardiovascular risk in postmenopausal women how to translate preclinical evidence into benefit for patients T2 - Kidney international : official journal of the International Society of Nephrology N2 - Preclinical work indicates that calcitriol restores vascular function by normalizing the endothelial expression of cyclooxygenase-2 and thromboxane-prostanoid receptors in conditions of estrogen deficiency and thus prevents the thromboxane-prostanoid receptor activation-induced inhibition of nitric oxide synthase. Since endothelial dysfunction is a key factor in the pathogenesis of cardiovascular diseases, this finding may have an important translational impact. It provides a clear rationale to use endothelial function in clinical trials aiming to find the optimal dose of vitamin D for the prevention of cardiovascular events in postmenopausal women. Y1 - 2013 U6 - https://doi.org/10.1038/ki.2013.139 SN - 0085-2538 VL - 84 IS - 1 SP - 9 EP - 11 PB - Nature Publ. Group CY - New York ER - TY - CHAP A1 - Hocher, Berthold A1 - Tsuprykov, Oleg A1 - Alter, Markus L. A1 - von Websky, Karoline A1 - Chaykovska, Lyubov A1 - Antonenko, V. A1 - Rahnenführer, Jan A1 - Klein, T. A1 - Reichetzeder, Christoph T1 - Linagliptin and the angiotensin II receptor blocker telmisartan show comparable efficacy but different renoprotective pathways in rats with 5/6 nephrectomy T2 - Diabetologia : journal of the European Association for the Study of Diabetes (EASD) Y1 - 2013 SN - 0012-186X SN - 1432-0428 VL - 56 IS - 15-16 SP - S66 EP - S66 PB - Springer CY - New York ER -