TY - JOUR A1 - Chaykovska, Lyubov A1 - Alter, Markus L. A1 - von Websky, Karoline A1 - Hohmann, Margarete A1 - Tsuprykov, Oleg A1 - Reichetzeder, Christoph A1 - Kutil, Barbara A1 - Kraft, Robin A1 - Klein, Thomas A1 - Hocher, Berthold T1 - Effects of telmisartan and linagliptin when used in combination on blood pressure and oxidative stress in rats with 2-kidney-1-clip hypertension JF - Journal of hypertension N2 - Objective:To investigate the effects of linagliptin alone and in combination with the angiotensin II receptor blocker (ARB), telmisartan on blood pressure (BP), kidney function, heart morphology and oxidative stress in rats with renovascular hypertension.Methods:Fifty-seven male Wistar rats underwent unilateral surgical stenosis of the renal artery [2-kidney-1-clip (2k1c) method]. Animals were randomly divided into four treatment groups (n=14-18 per group) receiving: telmisartan (10mg/kg per day in drinking water), linagliptin (89ppm in chow), combination (linagliptin 89ppm+telmisartan 10mg/kg per day) or placebo. An additional group of 12 rats underwent sham surgery. BP was measured one week after surgery. Hypertensive animals entered a 16-week dosing period. BP was measured 2, 4, 8, 12 and 16 weeks after the initiation of treatment. Blood and urine were tested for assessment of kidney function and oxidative stress 6, 10, 14 and 18 weeks after surgery. Blood and urine sampling and organ harvesting were finally performed.Results:Renal stenosis caused an increase in meanSD systolic BP as compared with the sham group (157.7 +/- 29.3 vs. 106.2 +/- 20.5mmHg, respectively; P<0.001). Telmisartan alone and in combination with linagliptin, normalized SBP (111.1 +/- 24.3mmHg and 100.4 +/- 13.9mmHg, respectively; P<0.001 vs. placebo). Telmisartan alone and in combination with linagliptin significantly prevented cardiac hypertrophy, measured by heart weight and myocyte diameter. Renal function measured by cystatin C was not affected by 2k1c surgery. Telmisartan significantly increased plasma concentration of cystatin C. 2k1c surgery initiated fibrosis in both kidneys. Telmisartan promoted further fibrotic changes in the clipped kidney, as measured by protein expression of Col1a1 and histology for interstitial fibrosis and glomerulosclerosis. In non-clipped kidneys, telmisartan demonstrated antifibrotic properties, reducing Col1a1 protein expression. Plasma levels of oxidized low-density lipoprotein were higher in the placebo-treated 2k1c rats as compared to sham-operated animals. The increase was abolished by linagliptin alone (P=0.03 vs. placebo) and in combination with telmisartan (P=0.02 vs. placebo). Combination therapy also significantly reduced plasma concentration of carbonyl proteins (P=0.04 vs. placebo).Conclusion:Inhibition of type 4 dipeptidyl peptidase with linagliptin did not counter BP-lowering effects of ARB in 2k1c rats. Linagliptin reduced lipid and protein oxidation in 2k1c rats, and this effect was BP-independent. KW - 2k1c renovascular hypertension KW - blood pressure KW - DPP4 inhibition KW - linagliptin KW - oxidative stress Y1 - 2013 U6 - https://doi.org/10.1097/HJH.0b013e3283649b4d SN - 0263-6352 SN - 1473-5598 VL - 31 IS - 11 SP - 2290 EP - 2299 PB - Lippincott Williams & Wilkins CY - Philadelphia ER - TY - JOUR A1 - Tepel, Martin A1 - Armbruster, Franz Paul A1 - Groen, Hans Juergen A1 - Scholze, Alexandra A1 - Reichetzeder, Christoph A1 - Roth, Heinz Jürgen A1 - Hocher, Berthold T1 - Nonoxidized, biologically active parathyroid hormone determines mortality in hemodialysis patients JF - The journal of clinical endocrinology & metabolism N2 - Background: It was shown that nonoxidized PTH (n-oxPTH) is bioactive, whereas the oxidation of PTH results in a loss of biological activity. Methods: In this study we analyzed the association of n-oxPTH on mortality in hemodialysis patients using a recently developed assay system. Results: Hemodialysis patients (224 men, 116 women) had a median age of 66 years. One hundred seventy patients (50%) died during the follow-up period of 5 years. Median n-oxPTH levels were higher in survivors (7.2 ng/L) compared with deceased patients (5.0 ng/L; P = .002). Survival analysis showed an increased survival in the highest n-oxPTH tertile compared with the lowest n-oxPTH tertile (chi(2), 14.3; P = 0008). Median survival was 1702 days in the highest n-oxPTH tertile, whereas it was only 453 days in the lowest n-oxPTH tertile. Multivariable-adjusted Cox regression showed that higher age increased odds for death, whereas higher n-oxPTH reduced the odds for death. Another model analyzing a subgroup of patients with intact PTH (iPTH) concentrations at baseline above the upper normal range of the iPTH assay (70 ng/L) revealed that mortality in this subgroup was associated with oxidized PTH but not with n-oxPTH levels. Conclusions: The predictive power of n-oxPTH and iPTH on the mortality of hemodialysis patients differs substantially. Measurements of n-oxPTH may reflect the hormone status more precisely. The iPTH-associated mortality is most likely describing oxidative stress-related mortality. Y1 - 2013 U6 - https://doi.org/10.1210/jc.2013-2139 SN - 0021-972X SN - 1945-7197 VL - 98 IS - 12 SP - 4744 EP - 4751 PB - Endocrine Society CY - Chevy Chase ER - TY - CHAP A1 - Hocher, Berthold A1 - Armbruster, Franz Paul A1 - Scholze, Alexandra A1 - Marckmann, Peter A1 - Reichetzeder, Christoph A1 - Roth, Heinz Jürgen A1 - Tepel, Martin T1 - Non-oxidized, biological active parathyroid hormone determines motality in hemodialsysis patients T2 - Nephrology, dialysis, transplantation Y1 - 2013 SN - 0931-0509 VL - 28 SP - 33 EP - 33 PB - Oxford Univ. Press CY - Oxford ER - TY - JOUR A1 - Li, Jian A1 - Wang, Zi-Neng A1 - Chen, You-Peng A1 - Dong, Yun-Peng A1 - Shuai, Han-Lin A1 - Xiao, Xiao-Min A1 - Reichetzeder, Christoph A1 - Hocher, Berthold T1 - Late gestational maternal serum cortisol is inversely associated with fetal brain growth JF - Neuroscience & biobehavioral reviews : official journal of the International Behavioral Neuroscience Society N2 - To analyze the association between fetal brain growth and late gestational blood serum cortisol in normal pregnancy.Blood total cortisol was quantified at delivery in 432 Chinese mother/child pairs. Key inclusion criteria of the cohort were: no structural anomalies of the newborn, singleton pregnancy, no alcohol abuse, no drug abuse or history of smoking no hypertensive disorders and no impairment of glucose tolerance and no use of steroid medication during pregnancy. Differential ultrasound examination of the fetal body was done in early (gestational day 89.95 +/- 7.31), middle (gestational day 160.17 16.12) and late pregnancy (gestational day 268.89 +/- 12.42). Newborn's cortisol was not correlated with any of the ultrasound measurements during pregnancy nor with birth weight. Multivariable regression analysis, considering timing of the ultrasound examination, the child's sex, maternal BMI, maternal age, maternal body weight at delivery, the timing of cortisol measurement and maternal uterine contraction states, revealed that maternal serum total cortisol was significantly negative correlated with ultrasound parameters describing the fetal brain: late biparietal diameter (R-2 =0.512, p =0.009), late head circumference (R-2 = 0.498, p= 0.001), middle biparietal diameter (R-2= 0.819, p = 0.013), middle cerebellum transverse diameter R-2 = 0.76, p= 0.014) and early biparietal diameter(R-2 = 0.819, p = 0.013). The same analysis revealed that birth weight as well as ultrasound parameters such as abdominal circumference and femur length were not correlated to maternal cortisol levels. In conclusion, our study demonstrates that maternal cortisol secretion within physiological ranges may be inversely correlated to fetal brain growth but not to birth weight. It remains to be demonstrated whether maternal cortisol secretion negatively influencing fetal brain growth translates to adverse neurological outcomes in later life. KW - Brain development KW - Fetal programming KW - Cortisol Maternal cortisol KW - Head circumference KW - Biparietal diameter Y1 - 2012 U6 - https://doi.org/10.1016/j.neubiorev.2011.12.006 SN - 0149-7634 VL - 36 IS - 3 SP - 1085 EP - 1092 PB - Elsevier CY - Oxford ER - TY - CHAP A1 - Hocher, Berthold A1 - Reichetzeder, Christoph A1 - von Websky, Karoline A1 - Tsuprykov, Oleg A1 - Klein, T. T1 - Dipeptidyl peptidase-4 inhibition in a rat model of ischaemia-reperfusion injury may accelerate tubular regeneration but does not improve glomerular filtration rate T2 - Diabetologia : journal of the European Association for the Study of Diabetes (EASD) Y1 - 2014 SN - 0012-186X SN - 1432-0428 VL - 57 SP - S538 EP - S538 PB - Springer CY - New York ER - TY - CHAP A1 - Reichetzeder, Christoph A1 - Pasch, A. A1 - von Websky, Karoline A1 - Tsuprykov, Oleg A1 - Klein, T. A1 - Hocher, Berthold T1 - The DPP-4 inhibitor linagliptin increases plasma fetuin-A concentrations in a rat model of uraemic calcification T2 - Diabetologia : journal of the European Association for the Study of Diabetes (EASD) Y1 - 2014 SN - 0012-186X SN - 1432-0428 VL - 57 SP - S522 EP - S522 PB - Springer CY - New York ER - TY - JOUR A1 - Sharkovska, Yuliya A1 - Reichetzeder, Christoph A1 - Alter, Markus L. A1 - Tsuprykov, Oleg A1 - Bachmann, Sebastian A1 - Secher, Thomas A1 - Klein, Thomas A1 - Hocher, Berthold T1 - Blood pressure and glucose independent renoprotective effects of dipeptidyl peptidase-4 inhibition in a mouse model of type-2 diabetic nephropathy JF - Journal of hypertension N2 - 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. KW - diabetic nephropathy KW - DPP-4 inhibitors KW - linagliptin Y1 - 2014 U6 - https://doi.org/10.1097/HJH.0000000000000328 SN - 0263-6352 SN - 1473-5598 VL - 32 IS - 11 SP - 2211 EP - 2223 PB - Lippincott Williams & Wilkins CY - Philadelphia ER - TY - JOUR A1 - Reichetzeder, Christoph A1 - Chen, Hong A1 - Foeller, 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 - lessons learned from humans and mice JF - Kidney & blood pressure research : official organ of the Gesellschaft für Nephrologie N2 - 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. KW - Vitamin D KW - Birth weight KW - Preterm delivery KW - Fetal programming KW - Glucose tolerance KW - Cardiovascular diseases Y1 - 2014 U6 - https://doi.org/10.1159/000355809 SN - 1420-4096 SN - 1423-0143 VL - 39 IS - 4 SP - 315 EP - 329 PB - Karger CY - Basel ER - TY - JOUR A1 - Putra, Sulistyo Emantoko Dwi A1 - Tsuprykov, Oleg A1 - Von Websky, Karoline A1 - Ritter, Teresa A1 - Reichetzeder, Christoph A1 - Hocher, Berthold T1 - Dealing with large sample sizes: comparison of a new one spot dot blot method to western blot JF - Clinical laboratory : the peer reviewed journal for clinical laboratories and laboratories related to blood transfusion N2 - 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. KW - one dot two development signals (ODTDS) dot blot KW - western blot KW - protein quantification KW - large sample size studies KW - comparison Y1 - 2014 U6 - https://doi.org/10.7754/Clin.Lab.2014.140317 SN - 1433-6510 VL - 60 IS - 11 SP - 1871 EP - 1877 PB - Clin Lab Publ., Verl. Klinisches Labor CY - Heidelberg ER - TY - JOUR A1 - Chen, You-Peng A1 - Xiao, Xiao-Min A1 - Li, Jian A1 - Reichetzeder, Christoph A1 - Wang, Zi-Neng A1 - Hocher, Berthold T1 - Paternal body mass index (BMI) is associated with offspring intrauterine growth in a gender dependent manner JF - PLoS one N2 - Background: Environmental alternations leading to fetal programming of cardiovascular diseases in later life have been attributed to maternal factors. However, animal studies showed that paternal obesity may program cardio-metabolic diseases in the offspring. In the current study we tested the hypothesis that paternal BMI may be associated with fetal growth. Methods and Results: We analyzed the relationship between paternal body mass index (BMI) and birth weight, ultrasound parameters describing the newborn's body shape as well as parameters describing the newborns endocrine system such as cortisol, aldosterone, renin activity and fetal glycated serum protein in a birth cohort of 899 father/mother/child triplets. Since fetal programming is an offspring sex specific process, male and female offspring were analyzed separately. Multivariable regression analyses considering maternal BMI, paternal and maternal age, hypertension during pregnancy, maternal total glycated serum protein, parity and either gestational age (for birth weight) or time of ultrasound investigation (for ultrasound parameters) as confounding showed that paternal BMI is associated with growth of the male but not female offspring. Paternal BMI correlated with birth parameters of male offspring only: birth weight; biparietal diameter, head circumference; abdominal diameter, abdominal circumference; and pectoral diameter. Cortisol was likewise significantly correlated with paternal BMI in male newborns only. Conclusions: Paternal BMI affects growth of the male but not female offspring. Paternal BMI may thus represent a risk factor for cardiovascular diseases of male offspring in later life. It remains to be demonstrated whether this is linked to an offspring sex specific paternal programming of cortisol secretion. Y1 - 2012 U6 - https://doi.org/10.1371/journal.pone.0036329 SN - 1932-6203 VL - 7 IS - 5 PB - PLoS CY - San Fransisco ER - 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 - 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 - JOUR A1 - Hocher, Berthold A1 - Armbruster, Franz Paul A1 - Stöva, Stanka A1 - Reichetzeder, Christoph A1 - Groen, Hans Jürgen A1 - Lieker, Ina A1 - Khadzhynov, Dmytro A1 - Slowinski, Torsten A1 - Roth, Heinz Jürgen T1 - Measuring Parathyroid Hormone (PTH) in patients with oxidative stress - do we need a fourth generation Parathyroid Hormone assay? JF - PLoS one N2 - Oxidation of PTH at methionine residues results in loss of biological activity. PTH may be oxidized in patients with renal disease. The aim of this study was to develop an assay considering oxidation of PTH. Oxidized hPTH was analyzed by high resolution nano-liquid chromatography coupled to ESI-FTT tandem mass spectrometry (nanoLC-ESI-FT-MS/MS) directly and after proteolytic cleavage. The oxidized hPTH(1-84) sample shows TIC-peaks at 18-20 min and several mass peaks due to mass shifts caused by oxidations. No significant signal for oxidized hPTH(1-84) species after removal of oxidized PTH molecules by a specific column with monoclonal antibodies (MAB) raised against the oxidized hPTH was detectable. By using this column in samples from 18 patients on dialysis we could demonstrate that measured PTH concentrations were substantially lower when considering oxidized forms of PTH. The relationship between PTH concentrations determined directly and those concentrations measured after removal of the oxidized PTH forms varies substantially. In some patients only 7% of traditionally measured PTH was free of oxidation, whereas in other patients 34% of the traditionally measured PTH was real intact PTH. In conclusion, a huge but not constant proportion of PTH molecules are oxidized in patients requiring dialysis. Since oxidized PTH is biologically inactive, the currently used methods to detect PTH in daily clinical practice may not adequately reflect PTH-related bone and cardiovascular abnormalities in patients on dialysis. Y1 - 2012 U6 - https://doi.org/10.1371/journal.pone.0040242 SN - 1932-6203 VL - 7 IS - 7 PB - PLoS CY - San Fransisco ER - TY - JOUR A1 - Alter, Markus L. A1 - Kretschmer, Axel A1 - Von Websky, Karoline A1 - Tsuprykov, Oleg A1 - Reichetzeder, Christoph A1 - Simon, Alexandra A1 - Stasch, Johannes-Peter A1 - Hocher, Berthold T1 - Early urinary and plasma biomarkers for experimental diabetic Nephropathy JF - Clinical laboratory : the peer reviewed journal for clinical laboratories and laboratories related to blood transfusion N2 - Background: As the prevalence of diabetes rises, its complications such as diabetic nephropathy affect an increaseing number of patients. Consequently, the need for biomarkers in rodent models which reflect the stage and course of diabetic nephropathy is high. This article focuses on Heart-type fatty acid binding protein (H-FABP), osteopontin (OPN), nephrin, and Neutrophil gelatinase-associated lipocalin (NGAL) in urine, and kidney injury molecule (KIM)-1, clusterin, and tissue inhibitior of metalloproteinases (TIMP) 1 in plasma in uni-nephrectomized rats with streptocotozin-induced type 1 diabetes mellitus, a common animal model to explore renal impairment in the setting of diabetes mellitus. Methods: 23 male Wistar rats were uni-nephrectomized and subsequently divided into two study groups. The diabetic group received streptozotocin (STZ) via tail-vein injection, the non-diabetic group received citrate buffer without STZ. Subsequently, blood glucose, body weight, and blood pressure were checked regularly. After 18 weeks, animals were placed in metabolic cages, blood and urine obtained and subsequently organs were harvested after sacrifice. Results: Blood glucose levels were highly increased in diabetic animals throughout the experiment, whereas systolic blood pressure did not differ between the study groups. At study end, classical biomarkers such as urinary albumin and protein and plasma cystatin c were only slightly but not significantly different between groups indicating a very early disease state. In contrast, urinary excretion of H-FABP, OPN, nephrin, and NGAL were highly increased in diabetic animals with a highly significant p-value (p<0.01 each) compared to non-diabetic animals. In plasma, differences were found for calbindin, KIM-1, clusterin, TIMP-1, and OPN. These findings were confirmed by means of the area under the receiver operating characteristic curve (ROC-AUC) analysis. Conclusions: In summary, our study revealed elevated levels of new plasma and urinary biomarkers (urinary osteopontin, urinary nephrin, urinary NGAL, urinary H-FABP, plasma KIM-1, plasma TIMP-1) in uni-nephrectomized diabetic rats, an established rat model of diabetic nephropathy. These biomarkers appeared even before the classical biomarkers of diabetic nephropathy such as albuminuria and urinary protein excretion. The new biomarkers might offer advantage to urinary albumin and plasma cystatin c with respect to early detection. KW - diabetic nephropathy KW - urinary biomarker KW - blood biomarker KW - heart-type fatty acid binding protein KW - osteopontin KW - nephrin KW - neutrophil gelatinase-associated lipocalin KW - kidney injury molecule 1 KW - clusterin KW - tissue inhibitior of metalloproteinases 1 Y1 - 2012 U6 - https://doi.org/10.7754/Clin.Lab.2011.111010 SN - 1433-6510 VL - 58 IS - 7-8 SP - 659 EP - 671 PB - Clin Lab Publ., Verl. Klinisches Labor CY - Heidelberg ER - TY - JOUR A1 - Chen, You-Peng A1 - Li, Jian A1 - Wang, Zi-Neng A1 - Reichetzeder, Christoph A1 - Xu, Hao A1 - Gong, Jian A1 - Chen, Guang-Ji A1 - Pfab, Thiemo A1 - Xiao, Xiao-Min A1 - Hocher, Berthold T1 - Renin angiotensin aldosterone system and glycemia in pregnancy JF - Clinical laboratory : the peer reviewed journal for clinical laboratories and laboratories related to blood transfusion N2 - Background: The renin-angiotensin-aldosterone system (RAAS) is involved in the pathogenesis of insulin resistance and type 2 diabetes in the general population. The RAAS is activated during pregnancy. However, it is unknown whether the RAAS contributes to glycemia in pregnant women. Methods: Plasma renin activity (PRA) and plasma aldosterone levels were quantified at delivery in 689 Chinese mothers. An oral glucose tolerance test in fasted women was performed in the second trimester of pregnancy. The diagnosis of gestational diabetes mellitus (GDM) and impaired glucose tolerance during pregnancy were made according to the guidelines of the Chinese Society of Obstetrics. Results: Plasma aldosterone was significantly higher in pregnant women with GDM as compared to those without impairment of glycemic control (normal pregnancies: 0.27 +/- 0.21 ng/mL, GDM: 0.36 +/- 0.30 ng/mL; p<0.05). Regression analyses revealed that PRA was negatively correlated with fasting blood glucose (FBG) (R-2 = 0.03, p = 0.007), whereas plasma aldosterone and aldosterone/PRA ratio were positively correlated with FBG (R-2 = 0.05, p<0.001 and R-2 = 0.03, p = 0.007, respectively). Multivariable regression analysis models considering relevant confounding factors confirmed these findings. Conclusions: This study demonstrated that fasting blood glucose in pregnant women is inversely correlated with the PRA, whereas plasma aldosterone showed a highly significant positive correlation with fasting blood glucose during pregnancy. Moreover, plasma aldosterone is significantly higher in pregnant women with GDM as compared to those women with normal glucose tolerance during pregnancy. Although causality cannot be proven in association studies, these data may indicate that the RAAS during pregnancy contributes to the pathogenesis of insulin resistance/new onset of diabetes during pregnancy. KW - Renin-angiotensin-aldosterone system KW - pregnancy KW - fasting blood glucose KW - glycemic control Y1 - 2012 SN - 1433-6510 VL - 58 IS - 5-6 SP - 527 EP - 533 PB - Clin Lab Publ., Verl. Klinisches Labor CY - Heidelberg 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 - Hocher, Berthold A1 - Reichetzeder, Christoph A1 - Alter, Markus L. T1 - Renal and cardiac effects of DPP-4 inhibitors - from preclinical development to clinical research JF - Kidney & blood pressure research : official organ of the Gesellschaft für Nephrologie N2 - Inhibitors of type 4 dipeptidyl peptidase (DDP-4) were developed and approved for the oral treatment of type 2 diabetes. Its mode of action is to inhibit the degradation of incretins, such as type 1 glucagon like peptide (GLP-1), and GIP. GLP-1 stimulates glucose-dependent insulin secretion from pancreatic beta-cells and suppresses glucagon release from alpha-cells, thereby improving glucose control. Besides its action on the pancreas type 1 glucagon like peptide has direct effects on the heart, vessels and kidney mainly via the type 1 glucagon like peptide receptor (GLP-1R). Moreover, there are substrates of DPP-4 beyond incretins that have proven renal and cardiovascular effects such as BNP/ANP, NPY, PYY or SDF-1 alpha. Preclinical evidence suggests that DPP-4 inhibitors may be effective in acute and chronic renal failure as well as in cardiac diseases like myocardial infarction and heart failure. Interestingly, large cardiovascular meta-analyses of combined Phase II/III clinical trials with DPP-4 inhibitors point all in the same direction: a potential reduction of cardiovascular events in patients treated with these agents. A pooled analysis of pivotal Phase III, placebo-controlled, registration studies of linagliptin further showed a significant reduction of urinary albumin excretion after 24 weeks of treatment. The observation suggests direct renoprotective effects of DPP-4 inhibition that may go beyond its glucose-lowering potential. Type 4 dipeptidyl peptidase inhibitors have been shown to be very well tolerated in general, but for those excreted via the kidney dose adjustments according to renal function are needed to avoid side effects. In conclusion, the direct cardiac and renal effects seen in preclinical studies as well as meta-analysis of clinical trials may offer additional potentials - beyond improvement of glycemic control - for this newer class of drugs, such as acute kidney failure, chronic kidney failure as well as acute myocardial infarction and heart failure. KW - DDP-4 inhibition KW - Diabetes KW - GLP-1 KW - Cardiovascular effects KW - Myocardial infarction KW - Kidney KW - Diabetic nephropathy KW - Acute renal failure Y1 - 2012 U6 - https://doi.org/10.1159/000339028 SN - 1420-4096 VL - 36 IS - 1 SP - 65 EP - 84 PB - Karger CY - Basel ER - TY - CHAP A1 - Sharkovska, Y. A1 - Alter, Markus L. A1 - Reichetzeder, Christoph A1 - Tsuprykov, Oleg A1 - Klein, T. A1 - Hocher, Berthold T1 - DPP-4 inhibition with linagliptin delays the progression of diabetic nephropathy in db/db mice T2 - Diabetologia : journal of the European Association for the Study of Diabetes (EASD) Y1 - 2012 SN - 0012-186X SN - 1432-0428 VL - 55 IS - 5 SP - S20 EP - S20 PB - Springer CY - New York 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 -