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  - 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  - 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  - 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  - 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  - Tsuprykov, Oleg
A1  - Ando, Ryotaro
A1  - Reichetzeder, Christoph
A1  - von Websky, Karoline
A1  - Antonenko, Viktoriia
A1  - Sharkovska, Yuliya
A1  - Chaykovska, Lyubov
A1  - Rahnenfuehrer, Jan
A1  - Hasan, Ahmed Abdallah Abdalrahman Mohamed
A1  - Tammen, Harald
A1  - Alter, Markus L.
A1  - Klein, Thomas
A1  - Ueda, Seiji
A1  - Yamagishi, Sho-ichi
A1  - Okuda, Seiya
A1  - Hocher, Berthold
T1  - The dipeptidyl peptidase inhibitor linagliptin and the angiotensin II receptor blocker telmisartan show renal benefit by different pathways in rats with 5/6 nephrectomy
JF  - Kidney international : official journal of the International Society of Nephrology
N2  - Dipeptidyl peptidase (DPP)-4 inhibitors delay chronic kidney disease (CKD) progression in experimental diabetic nephropathy in a glucose-independent manner. Here we compared the effects of the DPP-4 inhibitor linagliptin versus telmisartan in preventing CKD progression in non-diabetic rats with 5/6 nephrectomy. Animals were allocated to 1 of 4 groups: sham operated plus placebo; 5/6 nephrectomy plus placebo; 5/6 nephrectomy plus linagliptin; and 5/6 nephrectomy plus telmisartan. Interstitial fibrosis was significantly decreased by 48% with linagliptin but a non-significant 24% with telmisartan versus placebo. The urine albumin-to-creatinine ratio was significantly decreased by 66% with linagliptin and 92% with telmisartan versus placebo. Blood pressure was significantly lowered by telmisartan, but it was not affected by linagliptin. As shown by mass spectrometry, the number of altered peptide signals for linagliptin in plasma was 552 and 320 in the kidney. For telmisartan, there were 108 peptide changes in plasma and 363 in the kidney versus placebo. Linagliptin up-regulated peptides derived from collagen type I, apolipoprotein C1, and heterogeneous nuclear ribonucleoproteins A2/B1, a potential downstream target of atrial natriuretic peptide, whereas telmisartan up-regulated angiotensin II. A second study was conducted to confirm these findings in 5/6 nephrectomy wild-type and genetically deficient DPP-4 rats treated with linagliptin or placebo. Linagliptin therapy in wild-type rats was as effective as DPP-4 genetic deficiency in terms of albuminuria reduction. Thus, linagliptin showed comparable efficacy to telmisartan in preventing CKD progression in non-diabetic rats with 5/6 nephrectomy. However, the underlying pathways seem to be different. Copyright (C) 2016, International Society of Nephrology. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
KW  - albuminuria
KW  - angiotensin receptor blockers
KW  - chronic kidney disease
KW  - DPP-4 inhibition
KW  - proteinuria
KW  - proteomic analysis
Y1  - 2016
U6  - https://doi.org/10.1016/j.kint.2016.01.016
SN  - 0085-2538
SN  - 1523-1755
VL  - 89
SP  - 1049
EP  - 1061
PB  - Nature Publ. Group
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  - JOUR
A1  - Reichetzeder, Christoph
A1  - von Websky, Karoline
A1  - Tsuprykov, Oleg
A1  - Samarin, Azadeh Mohagheghi
A1  - Falke, Luise Gabriele
A1  - Putra, Sulistyo Emantoko Dwi
A1  - Hasan, Ahmed Abdallah Abdalrahman Mohamed
A1  - Antonenko, Viktoriia
A1  - Curato, Caterina
A1  - Rippmann, Joerg
A1  - Klein, Thomas
A1  - Hocher, Berthold
T1  - Head-to-head comparison of structurally unrelated dipeptidyl peptidase 4 inhibitors in the setting of renal ischemia reperfusion injury
JF  - British journal of pharmacology : journal of The British Pharmacological Society
N2  - BACKGROUND AND PURPOSE Results regarding protective effects of dipeptidyl peptidase 4 (DPP4) inhibitors in renal ischaemia-reperfusion injury (IRI) are conflicting. Here we have compared structurally unrelated DPP4 inhibitors in a model of renal IRI. EXPERIMENTAL APPROACH IRI was induced in uninephrectomizedmale rats by renal artery clamping for 30 min. The shamgroup was uninephrectomized but not subjected to IRI. DPP4 inhibitors or vehicle were given p. o. once daily on three consecutive days prior to IRI: linagliptin (1.5 mg.kg(-1).day(-1)), vildagliptin (8mg.kg(-1).day(-1)) and sitagliptin (30 mg.kg(-1).day(-1)). An additional group received sitagliptin until study end (before IRI: 30 mg.kg(-1).day(-1); after IRI: 15mg.kg(-1).day(-1)). KEY RESULTS Plasma-active glucagon-like peptide type 1 (GLP(-1)) increased threefold to fourfold in all DPP4 inhibitor groups 24 h after IRI. Plasma cystatin C, a marker of GFR, peaked 48 h after IRI. Compared with the placebo group, DPP4 inhibition did not reduce increased plasma cystatin C levels. DPP4 inhibitors ameliorated histopathologically assessed tubular damage with varying degrees of drug-specific efficacies. Renal osteopontin expression was uniformly reduced by all DPP4 inhibitors. IRI-related increased renal cytokine expression was not decreased by DPP4 inhibition. Renal DPP4 activity at study end was significantly inhibited in the linagliptin group, but only numerically reduced in the prolonged/dose-adjusted sitagliptin group. Active GLP(-1) plasma levels at study end were increased only in the prolonged/dose-adjusted sitagliptin treatment group. CONCLUSIONS AND IMPLICATIONS In rats with renal IRI, DPP4 inhibition did not alter plasma cystatin C, a marker of glomerular function, but may protect against tubular damage.
Y1  - 2017
U6  - https://doi.org/10.1111/bph.13822
SN  - 0007-1188
SN  - 1476-5381
VL  - 174
SP  - 2273
EP  - 2286
PB  - Wiley
CY  - Hoboken
ER  - 
TY  - JOUR
A1  - Hocher, Berthold
A1  - Lu, Yong-Ping
A1  - Reichetzeder, Christoph
A1  - Zhang, Xiaoli
A1  - Tsuprykov, Oleg
A1  - Rahnenführer, Jan
A1  - Xie, Li
A1  - Li, Jian
A1  - Hu, Liang
A1  - Krämer, Bernhard K.
A1  - Hasan, Ahmed A.
T1  - Paternal eNOS deficiency in mice affects glucose homeostasis and liver glycogen in male offspring without inheritance of eNOS deficiency itself
JF  - Diabetologia
N2  - Aims/hypothesis It was shown that maternal endothelial nitric oxide synthase (eNOS) deficiency causes fatty liver disease and numerically lower fasting glucose in female wild-type offspring, suggesting that parental genetic variants may influence the offspring's phenotype via epigenetic modifications in the offspring despite the absence of a primary genetic defect. The aim of the current study was to analyse whether paternal eNOS deficiency may cause the same phenotype as seen with maternal eNOS deficiency. Methods Heterozygous (+/-) male eNOS (Nos3) knockout mice or wild-type male mice were bred with female wild-type mice. The phenotype of wild-type offspring of heterozygous male eNOS knockout mice was compared with offspring from wild-type parents. Results Global sperm DNA methylation decreased and sperm microRNA pattern altered substantially. Fasting glucose and liver glycogen storage were increased when analysing wild-type male and female offspring of +/- eNOS fathers. Wild-type male but not female offspring of +/- eNOS fathers had increased fasting insulin and increased insulin after glucose load. Analysing candidate genes for liver fat and carbohydrate metabolism revealed that the expression of genes encoding glucocorticoid receptor (Gr; also known as Nr3c1) and peroxisome proliferator-activated receptor gamma coactivator 1-alpha (Pgc1a; also known as Ppargc1a) was increased while DNA methylation of Gr exon 1A and Pgc1a promoter was decreased in the liver of male wild-type offspring of +/- eNOS fathers. The endocrine pancreas in wild-type offspring was not affected. <br /> Conclusions/interpretation Our study suggests that paternal genetic defects such as eNOS deficiency may alter the epigenome of the sperm without transmission of the paternal genetic defect itself. In later life wild-type male offspring of +/- eNOS fathers developed increased fasting insulin and increased insulin after glucose load. These effects are associated with increased Gr and Pgc1a gene expression due to altered methylation of these genes.
KW  - eNOS
KW  - Glucocorticoid receptor
KW  - Insulin resistance
KW  - Paternal programming;
KW  - PGC1a
Y1  - 2022
U6  - https://doi.org/10.1007/s00125-022-05700-x
SN  - 0012-186X
SN  - 1432-0428
VL  - 65
IS  - 7
SP  - 1222
EP  - 1236
PB  - Springer
CY  - New York
ER  -