TY - JOUR A1 - Reichetzeder, Christoph A1 - Tsuprykov, Oleg A1 - Hocher, Berthold T1 - Endothelin receptor antagonists in clinical research - Lessons learned from preclinical and clinical kidney studies JF - Life sciences : molecular, cellular and functional basis of therapy N2 - Endothelin receptor antagonists (ETRAs) are approved for the treatment of pulmonary hypertension and scleroderma-related digital ulcers. The efforts to approve this class of drugs for renal indications, however, failed so far. Preclinical studies were promising. Transgenic overexpression of ET-1 or ET-2 in rodents causes chronic renal failure. Blocking the ET system was effective in the treatment of renal failure in rodent models. However, various animal studies indicate that blocking the renal tubular ETAR and ETBR causes water and salt retention partially mediated via the epithelial sodium transporter in tubular cells. ETRAs were successfully tested clinically in renal indications in phase 2 trials for the treatment of diabetic nephropathy. They showed efficacy in terms of reducing albumin excretion on top of guideline based background therapy (RAS blockade). However, these promising results could not be translated to successful phase Ill trials so far. The spectrum of serious adverse events was similar to other phase III trials using ETRAs. Potential underlying reasons for these failures and options to solve these issues are discussed. In addition preclinical and clinical studies suggest caution when addressing renal patient populations such as patients with hepatorenal syndrome, patients with any type of cystic kidney disease and patients at risk of contrast media induced nephropathy. The lessons learned in renal indications are also important for other potential promising indications of ETRAs like cancer and heart failure. (C) 2014 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/). KW - Endothelin receptor antagonists KW - Kidney KW - Side effects KW - Safety KW - Water and salt retention KW - Clinical trials Y1 - 2014 U6 - https://doi.org/10.1016/j.lfs.2014.02.025 SN - 0024-3205 SN - 1879-0631 VL - 118 IS - 2 SP - 141 EP - 148 PB - Elsevier CY - Oxford ER - TY - JOUR A1 - Chen, You-Peng A1 - Lu, Yong-Ping A1 - Li, Jian A1 - Liu, Zhi-Wei A1 - Chen, Wen-Jing A1 - Liang, Xu-Jing A1 - Chen, Xin A1 - Wen, Wang-Rong A1 - Xiao, Xiao-Min A1 - Reichetzeder, Christoph A1 - Hocher, Berthold T1 - Fetal and maternal angiotensin (1-7) are associated with preterm birth JF - Journal of hypertension N2 - Background: Recent studies show that preterm birth is associated with hypertension in later life. The renin-angiotensin system (RAS) during pregnancy influences fetal growth and development. In the current study, we investigated the impact of fetal as well as maternal angiotensin (1-7) [Ang (1-7)] and angiotensin II (Ang II) plasma concentrations on the risk of preterm birth. Methods: Three hundred and nine pregnant women were prospectively included into the study. The pregnant women were divided into two groups, for example, preterm birth of lower than 37 gestational weeks (n = 17) and full-term birth of 37 gestational weeks or more (n = 292). Maternal and neonatal plasma Ang (1-7) and Ang II concentrations were analyzed at birth from maternal venous blood and umbilical cord blood, respectively. Risk factors for premature birth were determined by multiple logistic regression analysis. Results: Fetal and maternal plasma Ang (1-7) concentrations in the preterm group were lower than those of the term group fetal Ang (1-7) preterm birth: 486.15 +/- 337.34 ng/l and fetal Ang (1-7) term birth: 833.84 +/- 698.12 ng/l and maternal Ang (1-7) preterm birth: 399.86 +/- 218.93 ng/l; maternal Ang (1-7) term birth: 710.34 +/- 598.22 ng/l. Multiple logistic regression analysis considering confounding factors revealed that preeclampsia (P < 0.001), premature rupture of membranes (P = 0.001), lower concentration of maternal Ang (1-7) (P = 0.013) and fetal plasma Ang (1-7) (P = 0.032) were independently associated with preterm birth. We could furthermore demonstrate that the maternal Ang (1-7)/Ang II ratio is independently associated with gestational hypertension or preeclampsia, factors causing preterm birth. Conclusions: Lower concentrations of maternal and fetal Ang (1-7) are independently associated with preterm birth - a risk factor of hypertension in later life. KW - angiotensin (1-7) KW - angiotensin II KW - cardiovascular disease KW - fetal programming KW - intrauterine fetal growth KW - pregnancy KW - preterm delivery Y1 - 2014 U6 - https://doi.org/10.1097/HJH.0000000000000251 SN - 0263-6352 SN - 1473-5598 VL - 32 IS - 9 SP - 1833 EP - 1841 PB - Lippincott Williams & Wilkins CY - Philadelphia ER - TY - JOUR A1 - von Websky, Karoline A1 - Reichetzeder, Christoph A1 - Hocher, Berthold T1 - Physiology and pathophysiology of incretins in the kidney JF - Current opinion in nephrology and hypertension : reviews of all advances, evaluations of key references, comprehensive listing of papers N2 - Purpose of reviewIncretin-based therapy with glucagon-like peptide-1 receptor (GLP-1R) agonists and dipeptidyl peptidase-4 (DPP-4) inhibitors is considered a promising therapeutic option for type 2 diabetes mellitus. Cumulative evidence, mainly from preclinical animal studies, reveals that incretin-based therapies also may elicit beneficial effects on kidney function. This review gives an overview of the physiology, pathophysiology, and pharmacology of the renal incretin system.Recent findingsActivation of GLP-1R in the kidney leads to diuretic and natriuretic effects, possibly through direct actions on renal tubular cells and sodium transporters. Moreover, there is evidence that incretin-based therapy reduces albuminuria, glomerulosclerosis, oxidative stress, and fibrosis in the kidney, partially through GLP-1R-independent pathways. Molecular mechanisms by which incretins exert their renal effects are understood incompletely, thus further studies are needed.SummaryThe GLP-1R and DPP-4 are expressed in the kidney in various species. The kidney plays an important role in the excretion of incretin metabolites and most GLP-1R agonists and DPP-4 inhibitors, thus special attention is required when applying incretin-based therapy in renal impairment. Preclinical observations suggest direct renoprotective effects of incretin-based therapies in the setting of hypertension and other disorders of sodium retention, as well as in diabetic and nondiabetic nephropathy. Clinical studies are needed in order to confirm translational relevance from preclinical findings for treatment options of renal diseases. KW - DDP-4 inhibition KW - diabetes KW - diabetic nephropathy KW - GLP-1 receptor KW - hypertension KW - incretins KW - kidney KW - renal impairment Y1 - 2014 U6 - https://doi.org/10.1097/01.mnh.0000437542.77175.a0 SN - 1062-4821 SN - 1473-6543 VL - 23 IS - 1 SP - 54 EP - 60 PB - Lippincott Williams & Wilkins CY - Philadelphia ER - TY - JOUR A1 - Zirafi, Onofrio A1 - Kim, Kyeong-Ae A1 - Ständker, Ludger A1 - Mohr, Katharina B. A1 - Sauter, Daniel A1 - Heigele, Anke A1 - Kluge, Silvia F. A1 - Wiercinska, Eliza A1 - Chudziak, Doreen A1 - Richter, Rudolf A1 - Möpps, Barbara A1 - Gierschik, Peter A1 - Vas, Virag A1 - Geiger, Hartmut A1 - Lamla, Markus A1 - Weil, Tanja A1 - Burster, Timo A1 - Zgraja, Andreas A1 - Daubeuf, Francois A1 - Frossard, Nelly A1 - Hachet-Haas, Muriel A1 - Heunisch, Fabian A1 - Reichetzeder, Christoph A1 - Galzi, Jean-Luc A1 - Perez-Castells, Javier A1 - Canales-Mayordomo, Angeles A1 - Jimenez-Barbero, Jesus A1 - Gimenez-Gallego, Guillermo A1 - Schneider, Marion A1 - Shorter, James A1 - Telenti, Amalio A1 - Hocher, Berthold A1 - Forssmann, Wolf-Georg A1 - Bonig, Halvard A1 - Kirchhoff, Frank A1 - Münch, Jan T1 - Discovery and Characterization of an Endogenous CXCR4 Antagonist JF - Cell reports N2 - CXCL12-CXCR4 signaling controls multiple physiological processes and its dysregulation is associated with cancers and inflammatory diseases. To discover as-yet-unknown endogenous ligands of CXCR4, we screened a blood-derived peptide library for inhibitors of CXCR4-tropic HIV-1 strains. This approach identified a 16 amino acid fragment of serum albumin as an effective and highly specific CXCR4 antagonist. The endogenous peptide, termed EPI-X4, is evolutionarily conserved and generated from the highly abundant albumin precursor by pH-regulated proteases. EPI-X4 forms an unusual lasso-like structure and antagonizes CXCL12-induced tumor cell migration, mobilizes stem cells, and suppresses inflammatory responses in mice. Furthermore, the peptide is abundant in the urine of patients with inflammatory kidney diseases and may serve as a biomarker. Our results identify EPI-X4 as a key regulator of CXCR4 signaling and introduce proteolysis of an abundant precursor protein as an alternative concept for chemokine receptor regulation. Y1 - 2015 U6 - https://doi.org/10.1016/j.celrep.2015.03.061 SN - 2211-1247 VL - 11 IS - 5 SP - 737 EP - 747 PB - Cell Press CY - Cambridge ER - TY - CHAP A1 - Reichetzeder, Christoph A1 - von Websky, Karoline A1 - Tsuprykov, Oleg A1 - Antonenko, V. A1 - Samarin, Azin Mohagheghi A1 - Hocher, Berthold T1 - Effects of DPP-4 inhibition on glomerular and tubular function in a rat model of ischaemia-reperfusion injury T2 - Diabetologia : journal of the European Association for the Study of Diabetes (EASD) Y1 - 2015 SN - 0012-186X SN - 1432-0428 VL - 58 SP - S34 EP - S35 PB - Springer CY - New York ER - TY - JOUR A1 - Tsuprykov, Oleg A1 - Chaykovska, Lyubov A1 - Kretschmer, Axel A1 - Stasch, Johannes-Peter A1 - Pfab, Thiemo A1 - Krause-Relle, Katharina A1 - Reichetzeder, Christoph A1 - Kalk, Philipp A1 - Adamski, Jerzy A1 - Hocher, Berthold T1 - Endothelin-1 overexpression improves renal function in eNOS knockout mice JF - Cellular physiology and biochemistry : international journal of experimental cellular physiology, biochemistry and pharmacology N2 - Background/Aims: To investigate the renal phenotype under conditions of an activated renal ET-1 system in the status of nitric oxide deficiency, we compared kidney function and morphology in wild-type, ET-1 transgenic (ET+/+), endothelial nitric oxide synthase knockout (eNOS-/-) and ET+/+eNOS-/- mice. Methods: We assessed blood pressure, parameters of renal morphology, plasma cystatin C, urinary protein excretion, expression of genes associated with glomerular filtration barrier and tissue remodeling, and plasma metabolites using metabolomics. Results: eNOS-/- and ET+/+eNOS-/- mice developed hypertension. Osteopontin, albumin and protein excretion were increased in eNOS-/- and restored in ET+/+eNOS-/- animals. All genetically modified mice developed renal interstitial fibrosis and glomerulosclerosis. Genes involved in tissue remodeling (serpinel, TIMP1, Collal, CCL2) were up-regulated in eNOS-/-, but not in ET+/+eNOS-/- mice. Plasma levels of free carnitine and acylcarnitines, amino acids, diacyl phosphatidylcholines, lysophosphatidylcholines and hexoses were descreased in eNOS-/- and were in the normal range in ET+/+eNOS-/- mice. Conclusion: eNOS-/- mice developed renal dysfunction, which was partially rescued by ET-1 overexpression in eNOS-/- mice. The metabolomics results suggest that ET-1 overexpression on top of eNOS knockout is associated with a functional recovery of mitochondria (rescue effect in 13-oxidation of fatty acids) and an increase in antioxidative properties (normalization of monounsaturated fatty acids levels). (C) 2015 The Author(s) Published by S. Karger AG, Basel KW - Chronic kidney disease KW - Endothelial nitric oxide synthase KW - Endothelin KW - Mice KW - Nitric oxide Y1 - 2015 U6 - https://doi.org/10.1159/000438516 SN - 1015-8987 SN - 1421-9778 VL - 37 IS - 4 SP - 1474 EP - 1490 PB - Karger CY - Basel ER - TY - CHAP A1 - Chen, Hong A1 - Reichetzeder, Christoph A1 - Föller, Michael A1 - Slowinski, Torsten A1 - Li, Jian A1 - Chen, You-Peng A1 - Lang, Florian A1 - Hocher, Berthold T1 - Maternal vitamin D deficiency and fetal programming T2 - Acta physiologica : official journal of the Federation of European Physiological Societies Y1 - 2015 SN - 1748-1708 SN - 1748-1716 VL - 213 SP - 155 EP - 156 PB - Wiley-Blackwell CY - Hoboken 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 - 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 - JOUR A1 - Li, Jian A1 - Lu, Yong Ping A1 - Reichetzeder, Christoph A1 - Kalk, Philipp A1 - Kleuser, Burkhard A1 - Adamski, Jerzy A1 - Hocher, Berthold T1 - Maternal PCaaC38:6 is Associated With Preterm Birth - a Risk Factor for Early and Late Adverse Outcome of the Offspring JF - Journal of European public policy N2 - Background/Aims: Preterm birth (PTB) and low birth weight (LBW) significantly influence mortality and morbidity of the offspring in early life and also have long-term consequences in later life. A better understanding of the molecular mechanisms of preterm birth could provide new insights regarding putative preventive strategies. Metabolomics provides a powerful analytic tool to readout complex interactions between genetics, environment and health and may serve to identify relevant biomarkers. In this study, the association between 163 targeted maternal blood metabolites and gestational age was investigated in order to find candidate biomarkers for PTB. Methods: Five hundred twenty-three women were included into this observational study. Maternal blood was obtained before delivery. The concentration of 163 maternal serum metabolites was measured by flow injection tandem mass spectrometry. To find putative biomarkers for preterm birth, a three-step analysis was designed: bivariate correlation analysis followed by multivariable regression analysis and a comparison of mean values among gestational age groups. Results: Bivariate correlation analysis showed that 2 acylcarnitines (C16:2, C2), 1 amino acids (xLeu), 8 diacyl-PCs (PCaaC36:4, PCaaC38:4, PCaaC38:5, PCaaC38:6, PCaaC40:4, PCaaC40:5, PCaaC40:6, PCaaC42:4), and 1 Acylalkyl-PCs (PCaeC40:5) were inversely correlated with gestational age. Multivariable regression analysis confounded for PTB history, maternal body mass index (BMI) before pregnancy, systolic blood pressure at the third trimester, and maternal body weight at the third trimester, showed that the diacyl-PC PCaaC38:6 was the only metabolite inversely correlated with gestational age. Conclusions: Maternal blood concentrations of PCaaC38:6 are independently associated with gestational age. (C) 2016 The Author(s) Published by S. Karger AG, Basel KW - Metabolomics KW - PCaaC38:6 KW - Biomarker KW - Preterm birth Y1 - 2016 U6 - https://doi.org/10.1159/000443428 SN - 1420-4096 SN - 1423-0143 VL - 41 SP - 250 EP - 257 PB - Karger CY - Basel ER -