@article{ChenLuLietal.2014, author = {Chen, You-Peng and Lu, Yong-Ping and Li, Jian and Liu, Zhi-Wei and Chen, Wen-Jing and Liang, Xu-Jing and Chen, Xin and Wen, Wang-Rong and Xiao, Xiao-Min and Reichetzeder, Christoph and Hocher, Berthold}, title = {Fetal and maternal angiotensin (1-7) are associated with preterm birth}, series = {Journal of hypertension}, volume = {32}, journal = {Journal of hypertension}, number = {9}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {0263-6352}, doi = {10.1097/HJH.0000000000000251}, pages = {1833 -- 1841}, year = {2014}, abstract = {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.}, language = {en} } @inproceedings{HocherReichetzedervonWebskyetal.2014, author = {Hocher, Berthold and Reichetzeder, Christoph and von Websky, Karoline and Tsuprykov, Oleg and Klein, T.}, title = {Dipeptidyl peptidase-4 inhibition in a rat model of ischaemia-reperfusion injury may accelerate tubular regeneration but does not improve glomerular filtration rate}, series = {Diabetologia : journal of the European Association for the Study of Diabetes (EASD)}, volume = {57}, booktitle = {Diabetologia : journal of the European Association for the Study of Diabetes (EASD)}, publisher = {Springer}, address = {New York}, issn = {0012-186X}, pages = {S538 -- S538}, year = {2014}, language = {en} } @article{PutraNeuberReichetzederetal.2014, author = {Putra, Sulistyo Emantoko Dwi and Neuber, Corinna and Reichetzeder, Christoph and Hocher, Berthold and Kleuser, Burkhard}, title = {Analysis of genomic DNA methylation levels in human placenta using liquid Chromatography-Electrospray ionization tandem mass spectrometry}, series = {Cellular physiology and biochemistry : international journal of experimental cellular physiology, biochemistry and pharmacology}, volume = {33}, journal = {Cellular physiology and biochemistry : international journal of experimental cellular physiology, biochemistry and pharmacology}, number = {4}, publisher = {Karger}, address = {Basel}, issn = {1015-8987}, doi = {10.1159/000358666}, pages = {945 -- 952}, year = {2014}, abstract = {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.}, language = {en} } @article{PutraTsuprykovVonWebskyetal.2014, author = {Putra, Sulistyo Emantoko Dwi and Tsuprykov, Oleg and Von Websky, Karoline and Ritter, Teresa and Reichetzeder, Christoph and Hocher, Berthold}, title = {Dealing with large sample sizes: comparison of a new one spot dot blot method to western blot}, series = {Clinical laboratory : the peer reviewed journal for clinical laboratories and laboratories related to blood transfusion}, volume = {60}, journal = {Clinical laboratory : the peer reviewed journal for clinical laboratories and laboratories related to blood transfusion}, number = {11}, publisher = {Clin Lab Publ., Verl. Klinisches Labor}, address = {Heidelberg}, issn = {1433-6510}, doi = {10.7754/Clin.Lab.2014.140317}, pages = {1871 -- 1877}, year = {2014}, abstract = {Background: Western blot is the gold standard method to determine individual protein expression levels. However, western blot is technically difficult to perform in large sample sizes because it is a time consuming and labor intensive process. Dot blot is often used instead when dealing with large sample sizes, but the main disadvantage of the existing dot blot techniques, is the absence of signal normalization to a housekeeping protein. Methods: In this study we established a one dot two development signals (ODTDS) dot blot method employing two different signal development systems. The first signal from the protein of interest was detected by horseradish peroxidase (HRP). The second signal, detecting the housekeeping protein, was obtained by using alkaline phosphatase (AP). Results: Inter-assay results variations within ODTDS dot blot and western blot and intra-assay variations between both methods were low (1.04 - 5.71\%) as assessed by coefficient of variation. Conclusions: ODTDS dot blot technique can be used instead of western blot when dealing with large sample sizes without a reduction in results accuracy.}, language = {en} } @article{ReichetzederChenFoelleretal.2014, author = {Reichetzeder, Christoph and Chen, Hong and Foeller, Michael and Slowinski, Torsten and Li, Jian and Chen, You-Peng and Lang, Florian and Hocher, Berthold}, title = {Maternal vitamin D deficiency and fetal programming - lessons learned from humans and mice}, series = {Kidney \& blood pressure research : official organ of the Gesellschaft f{\"u}r Nephrologie}, volume = {39}, journal = {Kidney \& blood pressure research : official organ of the Gesellschaft f{\"u}r Nephrologie}, number = {4}, publisher = {Karger}, address = {Basel}, issn = {1420-4096}, doi = {10.1159/000355809}, pages = {315 -- 329}, year = {2014}, abstract = {Background/Aims: Cardiovascular disease partially originates from poor environmental and nutritional conditions in early life. Lack of micronutrients like 25 hydroxy vitamin D-3 (25OHD) during pregnancy may be an important treatable causal factor. The present study explored the effect of maternal 25OHD deficiency on the offspring. Methods: We performed a prospective observational study analyzing the association of maternal 25OHD deficiency during pregnancy with birth outcomes considering confounding. To show that vitamin D deficiency may be causally involved in the observed associations, mice were set on either 25OHD sufficient or insufficient diets before and during pregnancy. Growth, glucose tolerance and mortality was analyzed in the F1 generation. Results: The clinical study showed that severe 25OHD deficiency was associated with low birth weight and low gestational age. ANCOVA models indicated that established confounding factors such as offspring sex, smoking during pregnancy and maternal BMI did not influence the impact of 25OHD on birth weight. However, there was a significant interaction between 25OHD and gestational age. Maternal 25OHD deficiency was also independently associated with low APGAR scores 5 minutes postpartum. The offspring of 25OHD deficient mice grew slower after birth, had an impaired glucose tolerance shortly after birth and an increased mortality during follow-up. Conclusions: Our study demonstrates an association between maternal 25OHD and offspring birth weight. The effect of 25OHD on birth weight seems to be mediated by vitamin D controlling gestational age. Results from an animal experiment suggest that gestational 25OHD insufficiency is causally linked to adverse pregnancy outcomes. Since birth weight and prematurity are associated with an adverse cardiovascular outcome in later life, this study emphasizes the need for novel monitoring and treatment guidelines of vitamin D deficiency during pregnancy.}, language = {en} } @inproceedings{ReichetzederPaschvonWebskyetal.2014, author = {Reichetzeder, Christoph and Pasch, A. and von Websky, Karoline and Tsuprykov, Oleg and Klein, T. and Hocher, Berthold}, title = {The DPP-4 inhibitor linagliptin increases plasma fetuin-A concentrations in a rat model of uraemic calcification}, series = {Diabetologia : journal of the European Association for the Study of Diabetes (EASD)}, volume = {57}, booktitle = {Diabetologia : journal of the European Association for the Study of Diabetes (EASD)}, publisher = {Springer}, address = {New York}, issn = {0012-186X}, pages = {S522 -- S522}, year = {2014}, language = {en} } @misc{ReichetzederTsuprykovHocher2014, author = {Reichetzeder, Christoph and Tsuprykov, Oleg and Hocher, Berthold}, title = {Endothelin receptor antagonists in clinical research - Lessons learned from preclinical and clinical kidney studies}, series = {Life sciences : molecular, cellular and functional basis of therapy}, volume = {118}, journal = {Life sciences : molecular, cellular and functional basis of therapy}, number = {2}, publisher = {Elsevier}, address = {Oxford}, issn = {0024-3205}, doi = {10.1016/j.lfs.2014.02.025}, pages = {141 -- 148}, year = {2014}, abstract = {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/).}, language = {en} } @article{SharkovskaReichetzederAlteretal.2014, author = {Sharkovska, Yuliya and Reichetzeder, Christoph and Alter, Markus L. and Tsuprykov, Oleg and Bachmann, Sebastian and Secher, Thomas and Klein, Thomas and Hocher, Berthold}, title = {Blood pressure and glucose independent renoprotective effects of dipeptidyl peptidase-4 inhibition in a mouse model of type-2 diabetic nephropathy}, series = {Journal of hypertension}, volume = {32}, journal = {Journal of hypertension}, number = {11}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {0263-6352}, doi = {10.1097/HJH.0000000000000328}, pages = {2211 -- 2223}, year = {2014}, abstract = {Background: Despite the beneficial effects of type 4 dipeptidyl peptidase (DPP-4) inhibitors on glucose levels, its effects on diabetic nephropathy remain unclear. Method: This study examined the long-term renoprotective effects of DPP-4 inhibitor linagliptin in db/db mice, a model of type 2 diabetes. Results were compared with the known beneficial effects of renin-angiotensin system blockade by enalapril. Ten-week-old male diabetic db/db mice were treated for 3 months with either vehicle (n = 10), 3 mg linagliptin/kg per day (n = 8), or 20 mg enalapril/kg per day (n = 10). Heterozygous db/m mice treated with vehicle served as healthy controls (n = 8). Results: Neither linagliptin nor enalapril had significant effects on the parameters of glucose metabolism or blood pressure in diabetic db/db mice. However, linagliptin treatment reduced albuminuria and attenuated kidney injury. In addition, expression of podocyte marker podocalyxin was normalized. We also analysed DPP-4 expression by immunofluorescence in human kidney biopsies and detected upregulation of DPP-4 in the glomeruli of patients with diabetic nephropathy, suggesting that our findings might be of relevance for human kidney disease as well. Conclusion: Treatment with DPP-4 inhibitor linagliptin delays the progression of diabetic nephropathy damage in a glucose-independent and blood-pressure-independent manner. The observed effects may be because of the attenuation of podocyte injury and inhibition of myofibroblast transformation.}, language = {en} } @misc{vonWebskyReichetzederHocher2014, author = {von Websky, Karoline and Reichetzeder, Christoph and Hocher, Berthold}, title = {Physiology and pathophysiology of incretins in the kidney}, series = {Current opinion in nephrology and hypertension : reviews of all advances, evaluations of key references, comprehensive listing of papers}, volume = {23}, journal = {Current opinion in nephrology and hypertension : reviews of all advances, evaluations of key references, comprehensive listing of papers}, number = {1}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {1062-4821}, doi = {10.1097/01.mnh.0000437542.77175.a0}, pages = {54 -- 60}, year = {2014}, abstract = {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.}, language = {en} }