TY - GEN A1 - Alter, Markus L. A1 - Ott, Ina A1 - von Websky, Karoline A1 - Tsuprykov, Oleg A1 - Sharkovska, Yuliya A1 - Krause-Relle, Katharina A1 - Raila, Jens A1 - Henze, Andrea A1 - Kretschmer, Axel A1 - Stasch, Johannes-Peter A1 - Hocher, Berthold T1 - Additional stimulation of sGC on top of standard treatment with ARB`s may offer a new therapeutic approach for the treatment of diabetic nephropathy resistant to ARB treatment alone T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Background Riociguat is the first of a new class of drugs, the soluble guanylate cyclase (sGC) stimulators. Riociguat has a dual mode of action: it sensitizes sGC to the body’s own NO and can also increase sGC activity in the absence of NO. The NO-sGC-pathway is impaired in many cardiovascular diseases such as heart failure, pulmonary hypertension and diabetic nephropathy (DN). DN leads to high cardiovascular morbidity and mortality. There is still a high unmet medical need. The urinary albumin excretion rate is a predictive biomarker for these clinical events. Therefore, we investigated the effect of riociguat, alone and in combination with the angiotensin II receptor antagonist (ARB) telmisartan on the progression of DN in diabetic eNOS knock out mice, a new model closely resembling human pathology. Methods Seventy-six male eNOS knockout C57BL/6J mice were divided into 4 groups after receiving intraperitoneal high-dose streptozotocin: telmisartan (1 mg/kg), riociguat (3 mg/kg), riociguat+telmisartan (3 and 1 mg/kg), and vehicle. Fourteen mice were used as non-diabetic controls. After 12 weeks, urine and blood were obtained and blood pressure measured. Glucose concentrations were highly increased and similar in all diabetic groups. Results Riociguat, alone (105.2 ± 2.5 mmHg; mean±SEM; n = 14) and in combination with telmisartan (105.0 ± 3.2 mmHg; n = 12), significantly reduced blood pressure versus diabetic controls (117.1 ± 2.2 mmHg; n = 14; p = 0.002 and p = 0.004, respectively), whereas telmisartan alone (111.2 ± 2.6 mmHg) showed a modest blood pressure lowering trend (p = 0.071; n = 14). The effects of single treatment with either riociguat (97.1 ± 15.7 µg/d; n = 13) or telmisartan (97.8 ± 26.4 µg/d; n = 14) did not significantly lower albumin excretion on its own (p = 0.067 and p = 0.101, respectively). However, the combined treatment led to significantly lower urinary albumin excretion (47.3 ± 9.6 µg/d; n = 12) compared to diabetic controls (170.8 ± 34.2 µg/d; n = 13; p = 0.004), and reached levels similar to non-diabetic controls (31.4 ± 10.1 µg/d, n = 12). Conclusion Riociguat significantly reduced urinary albumin excretion in diabetic eNOS knock out mice that were refractory to treatment with ARB’s alone. Patients with diabetic nephropathy refractory to treatment with ARB’s have the worst prognosis among all patients with diabetic nephropathy. Our data indicate that additional stimulation of sGC on top of standard treatment with ARB`s may offer a new therapeutic approach for patients with diabetic nephropathy resistant to ARB treatment. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 855 KW - pulmonary hypertension KW - diabetic nephropathy KW - diabetic control KW - telmisartan KW - guanylate cyclase Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-428250 SN - 1866-8372 IS - 855 ER - TY - JOUR A1 - Prommer, Hans-Ulrich A1 - Maurer, Johannes A1 - von Websky, Karoline A1 - Freise, Christian A1 - Sommer, Kerstin A1 - Nasser, Hamoud A1 - Samapati, Rudi A1 - Reglin, Bettina A1 - Guimaraes, Pedro A1 - Pries, Axel Radlach A1 - Querfeld, Uwe T1 - Chronic kidney disease induces a systemic microangiopathy, tissue hypoxia and dysfunctional angiogenesis JF - Scientific reports N2 - Chronic kidney disease (CKD) is associated with excessive mortality from cardiovascular disease (CVD). Endothelial dysfunction, an early manifestation of CVD, is consistently observed in CKD patients and might be linked to structural defects of the microcirculation including microvascular rarefaction. However, patterns of microvascular rarefaction in CKD and their relation to functional deficits in perfusion and oxygen delivery are currently unknown. In this in-vivo microscopy study of the cremaster muscle microcirculation in BALB/c mice with moderate to severe uremia, we show in two experimental models (adenine feeding or subtotal nephrectomy), that serum urea levels associate incrementally with a distinct microangiopathy. Structural changes were characterized by a heterogeneous pattern of focal microvascular rarefaction with loss of coherent microvascular networks resulting in large avascular areas. Corresponding microvascular dysfunction was evident by significantly diminished blood flow velocity, vascular tone, and oxygen uptake. Microvascular rarefaction in the cremaster muscle paralleled rarefaction in the myocardium, which was accompanied by a decrease in transcription levels not only of the transcriptional regulator HIF-1 alpha, but also of its target genes Angpt-2, TIE-1 and TIE-2, Flkt-1 and MMP-9, indicating an impaired hypoxia-driven angiogenesis. Thus, experimental uremia in mice associates with systemic microvascular disease with rarefaction, tissue hypoxia and dysfunctional angiogenesis. Y1 - 2018 U6 - https://doi.org/10.1038/s41598-018-23663-1 SN - 2045-2322 VL - 8 PB - Nature Publ. Group CY - London 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 - JOUR A1 - Alter, Markus L. A1 - Ott, Ina M. A1 - von Websky, Karoline A1 - Tsuprykov, Oleg A1 - Sharkovska, Yuliya A1 - Krause-Relle, Katharina A1 - Raila, Jens A1 - Henze, Andrea A1 - Klein, Thomas A1 - Hocher, Berthold T1 - DPP-4 Inhibition on top of angiotensin receptor blockade offers a new therapeutic approach for diabetic nephropathy JF - Kidney & blood pressure research : official organ of the Gesellschaft für Nephrologie N2 - Background: The need for an improved treatment for diabetic nephropathy is greatest in patients who do not adequately respond to angiotensin II receptor blockers (ARBs). This study investigated the effect of the novel dipeptidyl peptidase-4 inhibitor linagliptin alone and in combination with the ARB telmisartan on the progression of diabetic nephropathy in diabetic endothelial nitric oxide synthase (eNOS) knockout mice. Methods: Sixty male eNOS knockout C57BL/6J mice were divided into four groups after receiving intraperitoneal high-dose streptozotocin: telmisartan (1 mg/kg), linagliptin (3 mg/kg), linagliptin + telmisartan (3 mg/kg + 1 mg/kg) and vehicle. Fourteen mice were used as non-diabetic controls. Results: After 12 weeks, urine and blood were obtained and blood pressure measured. Glucose concentrations were increased and similar in all diabetic groups. Telmisartan alone reduced systolic blood pressure by 5.9 mmHg versus diabetic controls (111.2 +/- 2.3 mmHg vs 117.1 +/- 2.2 mmHg; mean +/- SEM; P = 0.071). Combined treatment significantly reduced albuminuria compared with diabetic controls (71.7 +/- 15.3 mu g/24 h vs 170.8 +/- 34.2 mu g/24 h; P = 0.017), whereas the effects of single treatment with either telmisartan (97.8 +/- 26.4 mu g/24 h) or linagliptin (120.8 +/- 37.7 mu g/24 h) were not statistically significant. DPP-4 inhibition, alone and in combination, led to significantly lower plasma osteopontin levels compared with telmisartan alone. Histological analysis revealed reduced glomerulosclerosis after Linagliptin alone and in combination with telmisartan in comparison to non treated diabetic animals (p < 0.01 and p < 0.05). Kidney malonaldehyde immune-reactivity, a marker of oxidative stress, was significantly lower in animals treated with linagliptin. Conclusions: DPP-4 inhibition on top of ARB treatment significantly reduced urinary albumin excretion and oxidative stress in diabetic eNOS knockout mice. Linagliptin on top of an angiotensin II receptor blocker may offer a new therapeutic approach for patients with diabetic nephropathy. KW - Diabetic nephropathy KW - DPP-4 inhibitor KW - Linagliptin KW - Renin-angiotensin system Y1 - 2012 U6 - https://doi.org/10.1159/000341487 SN - 1420-4096 VL - 36 IS - 1 SP - 119 EP - 130 PB - Karger CY - Basel ER - TY - JOUR A1 - Hocher, Berthold A1 - Heiden, S. A1 - von Websky, Karoline A1 - Rahnenführer, Jörg A1 - Kalk, Philipp A1 - Pfab, T. T1 - Dual endothelin-converting enzyme/neutral endopeptidase blockade in rats with D-galactosamine-induced liver failure JF - European journal of medical research : official organ "Deutsche AIDS-Gesellschaft" N2 - Secondary activation of the endothelin system is thought to be involved in toxic liver injury. This study tested the hypothesis that dual endothelin-converting enzyme / neutral endopeptidase blockade might: be able to attenuate acute toxic liver injury. Male Sprague-Dawley rats were implanted with subcutaneous minipumps to deliver the novel compound SLV338 (10 mg/kg*d) or vehicle. Four days later they received two intraperitoneal injections of D-galactosamine (1.3 g/kg each) or vehicle at an interval of 12 hours. The animals were sacrificed 48 hours after the first injection. Injection of D-galactosamine resulted in very severe liver injury, reflected by strongly elevated plasma liver enzymes, hepatic necrosis and inflammation, and a mortality rate of 42.9 %. SLV338 treatment did not show any significant effect on the extent of acute liver injury as judged from plasma parameters, hepatic histology and mortality. Plasma measurements of SLV338 confirmed adequate drug delivery. Plasma concentrations of big endothelin-1 and endothelin-1 were significantly elevated in animals with liver injury (5-fold and 62-fold, respectively). Plasma endothelin-1 was significantly correlated with several markers of liver injury. SLV338 completely prevented the rise of plasma big endothelin-1 (p<0.05) and markedly attenuated the rise of endothelin-1 (p = 0.055). In conclusion, dual endothelin-converting enzyme / neutral endopeptidase blockade by SLV338 did not significantly attenuate D-galactosamine-induced acute liver injury, although it largely prevented the activation of the endothelin system. An evaluation of SLV338 in a less severe model of liver injury would be of interest, since very severe intoxication might not be relevantly amenable to pharmacological interventions. KW - endothelin KW - endothelin-converting enzyme KW - neutral endopeptidase KW - D-galactosamine KW - acute liver failure Y1 - 2011 SN - 0949-2321 VL - 16 IS - 6 SP - 275 EP - 279 PB - Med. Scientific Publ. Holzapfel CY - München ER - TY - CHAP A1 - Pfab, T. A1 - Sharkovska, Yukiya A1 - Alter, Markus L. A1 - von Websky, Karoline A1 - Mark, M. A1 - Klein, T. A1 - Hocher, Berthold T1 - Effect of linagliptin on infarction size and cardiac function in rats after myocardial ischaemia reperfusion T2 - Diabetologia : journal of the European Association for the Study of Diabetes (EASD) Y1 - 2011 SN - 0012-186X VL - 54 SP - S329 EP - S329 PB - Springer CY - New York 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 - Chaykovska, Lyubov A1 - von Websky, Karoline A1 - Rahnenführer, Jan A1 - Alter, Markus L. A1 - Heiden, Susi A1 - Fuchs, Holger A1 - Runge, Frank A1 - Klein, Thomas A1 - Hocher, Berthold T1 - Effects of DPP-4 Inhibitors on the Heart in a Rat Model of Uremic Cardiomyopathy JF - PLoS one N2 - Background: Uremic cardiomyopathy contributes substantially to mortality in chronic kidney disease (CKD) patients. Glucagon-like peptide-1 (GLP-1) may improve cardiac function, but is mainly degraded by dipeptidyl peptidase-4 (DPP-4). Methodology/Principal Findings: In a rat model of chronic renal failure, 5/6-nephrectomized [5/6N] rats were treated orally with DPP-4 inhibitors (linagliptin, sitagliptin, alogliptin) or placebo once daily for 4 days from 8 weeks after surgery, to identify the most appropriate treatment for cardiac dysfunction associated with CKD. Linagliptin showed no significant change in blood level AUC(0-infinity) in 5/6N rats, but sitagliptin and alogliptin had significantly higher AUC(0-infinity) values; 41% and 28% (p=0.0001 and p=0.0324), respectively. No correlation of markers of renal tubular and glomerular function with AUC was observed for linagliptin, which required no dose adjustment in uremic rats. Linagliptin 7 mu mol/kg caused a 2-fold increase in GLP-1 (AUC 201.0 ng/l*h) in 5/6N rats compared with sham-treated rats (AUC 108.6 ng/l*h) (p=0.01). The mRNA levels of heart tissue fibrosis markers were all significantly increased in 5/6N vs control rats and reduced/normalized by linagliptin. Conclusions/Significance: DPP-4 inhibition increases plasma GLP-1 levels, particularly in uremia, and reduces expression of cardiac mRNA levels of matrix proteins and B-type natriuretic peptides (BNP). Linagliptin may offer a unique approach for treating uremic cardiomyopathy in CKD patients, with no need for dose-adjustment. Y1 - 2011 U6 - https://doi.org/10.1371/journal.pone.0027861 SN - 1932-6203 VL - 6 IS - 11 PB - PLoS CY - San Fransisco ER - TY - JOUR A1 - Chen, Yao A1 - Wang, Guang A1 - Wang, Xiao-yu A1 - Ma, Zheng-lai A1 - Chen, You-peng A1 - Chuai, Manli A1 - von Websky, Karoline A1 - Hocher, Berthold A1 - Yang, Xuesong T1 - Effects of high salt-exposure on the development of retina and lens in 5.5-Day Chick Embryo JF - Cellular physiology and biochemistry : international journal of experimental cellular physiology, biochemistry and pharmacology N2 - Background/Aims: Excess maternal salt intake during pregnancy may alter fetal development. However; our knowledge on how an increased salt intake during pregnancy influences fetal eye development is limited. In this study, we investigated the effects of high salt treatment on the developing eyes in chick embryos, especially focusing on the development of the retina and the lens. Methods: 5.5 day chick embryos were exposed to 280mosm/l (n=17), or 300mosm/l (n=16) NaCl. The treated embryos were then incubated for 96 hours before they were fixed with 4% paraformaldehyde for H&E staining, whole mount embryo immunostaining and TUNEL staining. BrdU and PH3 incorporation experiments were performed on the chick embryos after high salt treatment. RT-PCR analyses were conducted from chick retina tissues. Results: We demonstrated that high-salt treatment altered the size of eyes in chick embryos, induced malformation of the eyes and impaired the development of the lens and the retina. We found an impaired expression of Paired box 6 (PAX6) and neuronal cells in the developing retina as revealed by neurofilament immunofluorescent staining. There was a reduction in the number of BrdU-positive cells and PH3-positive cells in the retina, indicating an impaired cell proliferation with high salt treatment. High salt treatment also resulted in an increased number of TUNEL-positive cells in the retina, indicating a higher amount of cell death. RT-PCR data displayed that the expression of the pro-apoptotic molecule nerve growth factor (NGF) in chick retina was increased and CyclinD1 was reduced with high-salt treatment. The size of the lens was reduced and Pax6 expression in the lens was significantly inhibited. High salt treatment was detrimental to the migration of neural crest cells. Conclusion: Taken together; our study demonstrated that high salt exposure of 5.5 day chick embryos led to an impairment of retina and lens development, possibly through interfering with Pax6 expression. KW - Chick embryos KW - High osmolarity KW - Retina KW - Lens KW - Pax6 Y1 - 2014 U6 - https://doi.org/10.1159/000363044 SN - 1015-8987 SN - 1421-9778 VL - 34 IS - 3 SP - 804 EP - 817 PB - Karger CY - Basel ER - TY - JOUR A1 - Ott, Ina M. A1 - Alter, Markus L. A1 - von Websky, Karoline A1 - Kretschmer, Axel A1 - Tsuprykov, Oleg A1 - Sharkovska, Yuliya A1 - Krause-Relle, Katharina A1 - Raila, Jens A1 - Henze, Andrea A1 - Stasch, Johannes-Peter A1 - Hocher, Berthold T1 - Effects of Stimulation of Soluble Guanylate Cyclase on Diabetic Nephropathy in Diabetic eNOS Knockout Mice on Top of Angiotensin II Receptor Blockade JF - PLOS ONE N2 - The prevalence of diabetes mellitus and its complications, such as diabetic nephropathy (DN), is rising worldwide and prevention and treatment are therefore becoming increasingly important. Therapy of DN is particularly important for patients who do not adequately respond to angiotensin receptor blocker (ARB) treatment. Novel approaches include the stimulation of soluble guanylate cyclase (sGC) as it is reported to have beneficial effects on cardiac and renal damage. We aimed to investigate the effects of the sGC stimulator riociguat and ARB telmisartan on kidney function and structure in a hypertensive model of diabetic nephropathy. Seventy-six diabetic male eNOS knockout C57BL/6J mice were randomly divided after having received streptozotocin: telmisartan (1 mg/kg/d), riociguat (3 mg/kg/d), riociguat+telmisartan (3+1 mg/kg/d), and vehicle. Fourteen mice were used as non-diabetic controls. Treatment duration was 11 weeks. Glucose concentrations were increased and similar in all diabetic groups. Telmisartan insignificantly reduced blood pressure by 5.9 mmHg compared with diabetic controls (111.2 +/- 2.3 mmHg vs. 117.1 +/- 2.2 mmHg; p = 0.071). Treatment with riociguat both alone and in combination with telmisartan led to a significant reduction of blood pressure towards diabetic vehicle (105.2 +/- 2.5 mmHg and 105.0 +/- 3.2 mmHg, respectively, vs. 117.1 +/- 2.2 mmHg). Combined treatment also significantly decreased albuminuria compared with diabetic controls (47.3 +/- 9.6 mu g/24 h vs. 170.8 +/- 34.2 mu g/24 h; p = 0.002) reaching levels similar to those of non-diabetic controls (34.4 +/- 10.6 mu g/24 h), whereas the reduction by single treatment with either telmisartan (97.8 +/- 26.4 mu g/24 h) or riociguat (97.1 +/- 15.7 mu g/24 h) was not statistically significant. The combination treatment led to a significant (p < 0.01) decrease of tissue immunoreactivity of malondialdehyde, as consequence of reduced oxidative stress. In conclusion, stimulation of sGC significantly reduced urinary albumin excretion in diabetic eNOS knockout mice treated already with ARB. Thus, this new drug class on top of standard ARBs administration may offer a new therapeutic approach for patients resistant to ARB treatment. Y1 - 2012 U6 - https://doi.org/10.1371/journal.pone.0042623 SN - 1932-6203 VL - 7 IS - 8 PB - PUBLIC LIBRARY SCIENCE CY - SAN FRANCISCO ER -