@article{SharkovskaKalkLawrenzetal.2010, author = {Sharkovska, Yuliya and Kalk, Philipp and Lawrenz, Bettina and Godes, Michael and Hoffmann, Linda Sarah and Wellkisch, Kathrin and Geschka, Sandra and Relle, Katharina and Hocher, Berthold and Stasch, Johannes-Peter}, title = {Nitric oxide-independent stimulation of soluble guanylate cyclase reduces organ damage in experimental low- renin and high-renin models}, issn = {0263-6352}, doi = {10.1097/Hjh.0b013e32833b558c}, year = {2010}, abstract = {Objectives The nitric oxide-soluble guanylate cyclase (sGC)-cGMP signal transduction pathway is impaired in different cardiovascular diseases, including pulmonary hypertension, heart failure and arterial hypertension. Riociguat is a novel stimulator of soluble guanylate cyclase (sGC). However, little is known about the effects of sGC stimulators in experimental models of hypertension. We thus investigated the cardio-renal protective effects of riociguat in low- renin and high-renin rat models of hypertension. Methods The vasorelaxant effect of riociguat was tested in vitro on isolated saphenous artery rings of normal and nitrate tolerant rabbits. The cardiovascular in-vivo effects of sGC stimulation were evaluated in hypertensive renin-transgenic rats treated with the nitric oxide-synthase inhibitor N- nitro-L-arginine methyl ester (L-NAME) (high-renin model) and in rats with 5/6 nephrectomy (low-renin model). Results In both animal models, riociguat treatment improved survival and normalized blood pressure. Moreover, in the L-NAME study part, riociguat reduced cardiac target organ damage as indicated by lower plasma ANP, lower relative left ventricular weight and lower cardiac interstitial fibrosis, and reduced renal target organ damage as indicated by lower plasma creatinine and urea, less glomerulosclerosis and less renal interstitial fibrosis. In the 5/6 nephrectomy study part, riociguat reduced cardiac target organ damage as indicated by lower plasma ANP, lower relative left ventricular weight, lower myocyte diameter and lower arterial media/lumen ratio, and reduced renal target organ damage as indicated by improved creatinine clearance and less renal interstitial fibrosis. Conclusion We demonstrate for the first time that the novel sGC stimulator riociguat shows in two independent models of hypertension a potent protection against cardiac and renal target organ damage. J Hypertens 28: 1666-1675 (c) 2010 Wolters Kluwer Health vertical bar Lippincott Williams \& Wilkins.}, language = {en} } @article{KalkSharkovskaKashinaetal.2011, author = {Kalk, Philipp and Sharkovska, Yuliya and Kashina, Elena and von Websky, Karoline and Relle, Katharina and Pfab, Thiemo and Alter, Markus L. and Guillaume, Philippe and Provost, Daniel and Hoffmann, Katrin and Fischer, Yvan and Hocher, Berthold}, title = {Endothelin-Converting Enzyme/Neutral Endopeptidase Inhibitor SLV338 Prevents Hypertensive Cardiac Remodeling in a Blood Pressure-Independent Manner}, series = {HYPERTENSION}, volume = {57}, journal = {HYPERTENSION}, number = {4}, publisher = {LIPPINCOTT WILLIAMS \& WILKINS}, address = {PHILADELPHIA}, issn = {0194-911X}, doi = {10.1161/HYPERTENSIONAHA.110.163972}, pages = {755 -- 763}, year = {2011}, abstract = {Hypertensive heart disease is a major contributor to cardiovascular mortality. Endothelin is a potent vasoconstrictive and profibrotic mediator produced by the endothelin-converting enzyme (ECE), whereas natriuretic peptides, degraded by the neutral endopeptidase (NEP), have diuretic, vasodilatory, and antifibrotic properties. Thus, combined ECE/NEP inhibition may halt hypertensive cardiac remodeling. This study examined effects of SLV338, a novel ECE/NEP inhibitor, on cardiac protection in experimental renovascular hypertension (2-kidney, 1-clip [2K1C]). Male rats were allocated to 5 groups: sham-operated rats, untreated animals with 2K1C, 2K1C animals treated with oral SLV338 (30 and 100 mg/kg per day), and 2K1C animals treated with oral losartan (20 mg/kg per day). Treatment duration was 12 weeks. Blood pressure was assessed every 4 weeks. At study end, hearts were taken for histology/computer-aided histomorphometry/immunohistochemistry. Pharmacological properties of SLV338 are described. SLV338 is a dual ECE/NEP inhibitor, as demonstrated both in vitro and in vivo. In the 2K1C study, losartan lowered blood pressure by <= 46 mm Hg, whereas both dosages of SLV338 had no effect. However, SLV338 (both dosages) completely normalized cardiac interstitial fibrosis, perivascular fibrosis, myocyte diameter, and media: lumen ratio of cardiac arteries, as did losartan. Cardiac transforming growth factor-beta 1 expression was significantly enhanced in untreated 2K1C rats versus controls, whereas treatment with SLV338 and losartan prevented this effect. Taken together, dual ECE/NEP inhibitor SLV338 prevents cardiac remodeling to the same extent as losartan, but in a blood pressure-independent manner, in a rat model of renovascular hypertension. This effect is at least partially mediated via suppression of cardiac transforming growth factor-beta 1 expression. (Hypertension. 2011;57:755-763.)}, language = {en} } @article{VignonZellwegerRelleKienlenetal.2011, author = {Vignon-Zellweger, Nicolas and Relle, Katharina and Kienlen, Elodie and Alter, Markus L. and Seider, Patrick and Sharkovska, Juliya and Heiden, Susi and Kalk, Philipp and Schwab, Karima and Albrecht-Kuepper, Barbara and Theuring, Franz and Stasch, Johannes-Peter and Hocher, Berthold}, title = {Endothelin-1 overexpression restores diastolic function in eNOS knockout mice}, series = {Journal of hypertension}, volume = {29}, journal = {Journal of hypertension}, number = {5}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {0263-6352}, doi = {10.1097/HJH.0b013e3283450770}, pages = {961 -- 970}, year = {2011}, abstract = {Background The cardiac nitric oxide and endothelin-1 (ET-1) systems are closely linked and play a critical role in cardiac physiology. The balance between both systems is often disturbed in cardiovascular diseases. To define the cardiac effect of excessive ET-1 in a status of nitric oxide deficiency, we compared left ventricular function and morphology in wild-type mice, ET-1 transgenic (ET+/+) mice, endothelial nitric oxide synthase knockout (eNOS(-/-)) mice, and ET(+/+)eNOS(-/-) mice. Methods and results eNOS(-/-) and ET(+/+)eNOS(-/-) mice developed high blood pressure compared with wild-type and ET+/+ mice. Left ventricular catheterization showed that eNOS(-/-) mice, but not ET(+/+)eNOS(-/-), developed diastolic dysfunction characterized by increased end-diastolic pressure and relaxation constant tau. To elucidate the causal molecular mechanisms driving the rescue of diastolic function in ET(+/+)eNOS(-/-) mice, the cardiac proteome was analyzed. Two-dimensional gel electrophoresis coupled to mass spectrometry offers an appropriate hypothesis-free approach. ET-1 overexpression on an eNOS(-/-) background led to an elevated abundance and change in posttranslational state of antioxidant enzymes (e. g., peroxiredoxin-6, glutathione S-transferase mu 2, and heat shock protein beta 7). In contrast to ET(+/+)eNOS(-/-) mice, eNOS(-/-) mice showed an elevated abundance of proteins responsible for sarcomere disassembly (e. g., cofilin-1 and cofilin-2). In ET(+/+)eNOS(-/-) mice, glycolysis was favored at the expense of fatty acid oxidation. Conclusion eNOS(-/-) mice developed diastolic dysfunction; this was rescued by ET-1 transgenic overexpression. This study furthermore suggests that cardiac ET-1 overexpression in case of eNOS deficiency causes specifically the regulation of proteins playing a role in oxidative stress, myocytes contractility, and energy metabolism.}, language = {en} } @article{SharkovskaKalkvonWebskyetal.2011, author = {Sharkovska, Yuliya and Kalk, Philipp and von Websky, Karoline and Relle, Katharina and Pfab, Thiemo and Alter, Markus L. and Fischer, Yvan and Hocher, Berthold}, title = {Renoprotective effects of combined endothelin-converting enzyme/neutral endopeptidase inhibitor SLV338 in acute and chronic experimental renal damage}, series = {Clinical laboratory : the peer reviewed journal for clinical laboratories and laboratories related to blood transfusion}, volume = {57}, journal = {Clinical laboratory : the peer reviewed journal for clinical laboratories and laboratories related to blood transfusion}, number = {7-8}, publisher = {Clin Lab Publ., Verl. Klinisches Labor}, address = {Heidelberg}, issn = {1433-6510}, pages = {507 -- 515}, year = {2011}, abstract = {Background: Acute kidney injury (AKI) as well as chronic renal failure are associated with a huge mortality/morbidity. However, so far no drugs have been approved for the treatment of acute kidney failure and only a few for the treatment of chronic kidney disease (CKD). We analysed the effect of SLV 338, a neutral endopeptidase (NEP)/endothelin converting enzyme (ECE)-inhibitor in animal models of acute kidney failure as well as chronic renal failure. Methods: Acute renal failure was induced in male Wistar rats by uninephrectomy and clamping of the remaining kidney for 55 minutes. SLV338 (total dose: 4.9 mg/kg) or vehicle was continuously infused for 2 hours (starting 20 minutes prior to clamping). Sham operated animals served as controls. Plasma creatinine was measured at baseline and day 2 and 8 after renal ischemia-reperfusion. Hypertensive renal damage was induced in male Sprague Dawley rats by nitric oxide deficiency using L-NAME (50 mg/kg per day, added to drinking water for 4 weeks). One group was treated over the same time period with SLV338 (30 mg/kg per day, mixed with food). Systolic blood pressure was monitored weekly. At study end, urine and blood samples were collected and kidneys were harvested. Results: Acute renal ischemia-reperfusion caused a 5-fold plasma creatinine elevation (day 2), which was significantly attenuated by more than 50 \% in animals treated with SLV338 (p < 0.05). Renal failure was accompanied by a 67 \% mortality in vehicle-treated rats, but only 20 \% after SLV338 treatment (p = 0.03 compared to sham controls). Chronic L-NAME administration caused hypertension, urinary albumin excretion, glomerulosclerosis, renal arterial remodelling, and renal interstitial fibrosis. Treatment with SLV338 did not significantly affect blood pressure, but abolished renal tissue damage (interstitial fibrosis, glomerulosclerosis, renal arterial remodelling (p < 0.05 versus L-NAME group in each case). Conclusions: The dual ECE/NEP inhibitor SLV338 preserves kidney function and reduces mortality in severe acute ischemic renal failure. Moreover, combined ECE/NEP inhibition prevents hypertensive renal tissue damage in a blood pressure independent manner in L-NAME-treated rats.}, language = {en} } @article{VignonZellwegerRelleRahnenfuehreretal.2014, author = {Vignon-Zellweger, Nicolas and Relle, Katharina and Rahnenfuehrer, Jan and Schwab, Karima and Hocher, Berthold and Theuring, Franz}, title = {Endothelin-1 overexpression and endothelial nitric oxide synthase knock-out induce different pathological responses in the heart of male and female mice}, 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.2013.12.003}, pages = {219 -- 225}, year = {2014}, abstract = {Aims: The nitric oxide and endothelin systems are key components of a local paracrine hormone network in the heart. We previously reported that diastolic dysfunction observed in mice lacking the endothelial nitric oxide synthase (eNOS-/-) can be prevented by a genetic overexpression of ET-1. Sexual dimorphisms have been reported in both ET-1 and NO systems. Particularly, eNOS-/- mice present sex related phenotypic differences. Main methods: We used the ET-1 transgenic (ET+/+), eNOS-/-, and crossbred ET+/+ eNOS-/- mice, and wild type controls. We measured cardiac function by heart catheterization. Cardiac ventricles were collected for histological and molecular profiling. Key findings: We report here that (i) the level of ET-1 expression in eNOS-/- mice was elevated in males but not in females. (ii) Left ventricular end-diastolic blood pressure was higher in male eNOS-/- mice than in females. (ii) eNOS-/- males but not females developed cardiomyocyte hypertrophy. (iv) Perivascular fibrosis of intra-cardiac arteries developed in female ET+/+ and eNOS-/- mice but not in males. Additionally, (v) the cardiac expression of metalloprotease-9 was higher in eNOS-/- males compared to females. Finally, (vi) cardiac proteome analysis revealed that the protein abundance of the oxidative stress related enzyme superoxide dismutase presented with sexual dimorphism in eNOS-/- and ET+/+ mice. Significance: These results indicate that the cardiac phenotypes of ET-1 transgenic mice and eNOS knockout mice are sex specific. Since both systems are key players in the pathogenesis of cardiovascular diseases, our findings might be important in the context of gender differences in patients with such diseases. (C) 2013 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} }