@article{HechtFreisevonWebskyetal.2016, author = {Hecht, Eva and Freise, Christian and von Websky, Karoline and Nasser, Hamoud and Kretzschmar, Nadja and Stawowy, Philipp and Hocher, Berthold and Querfeld, Uwe}, title = {The matrix metalloproteinases 2 and 9 initiate uraemic vascular calcifications}, series = {Nephrology, dialysis, transplantation}, volume = {31}, journal = {Nephrology, dialysis, transplantation}, publisher = {Oxford Univ. Press}, address = {Oxford}, issn = {0931-0509}, doi = {10.1093/ndt/gfv321}, pages = {789 -- 797}, year = {2016}, abstract = {The matrix metalloproteinases (MMP) MMP-2 and MMP-9 are physiological regulators of vascular remodelling. Their dysregulation could contribute to vascular calcification. We examined the role of the MMP-2 and MMP-9 in uraemic vascular calcification in vivo and in vitro. The impact of pharmacological MMP inhibition on the development of media calcifications was explored in an aggressive animal model of uraemic calcification. In addition, the selective effects of addition and inhibition, respectively, of MMP-2 and MMP-9 on calcium-/phosphate-induced calcifications were studied in a murine cell line of vascular smooth muscle cells (VSMCs). High-dose calcitriol treatment of uraemic rats given a high phosphate diet induced massive calcifications, apoptosis and increased gene expressions of MMP-2, MMP-9 and of osteogenic transcription factors and proteins in aortic VSMC. The MMP inhibitor doxycycline prevented the VSMC transdifferentiation to osteoblastic cells, suppressed transcription of mediators of matrix remodelling and almost completely blocked aortic calcifications while further increasing apoptosis. Similarly, specific inhibitors of either MMP-2 or -9, or of both gelatinases (Ro28-2653) and a selective knockdown of MMP-2/-9 mRNA expression blocked calcification of murine VSMC induced by calcification medium (CM). In contrast to MMP inhibition, recombinant MMP-2 or MMP-9 enhanced CM-induced calcifications and the secretion of gelatinases. These data indicate that both gelatinases provide essential signals for phenotypic VSMC conversion, matrix remodelling and the initiation of vascular calcification. Their inhibition seems a promising strategy in the prevention of vascular calcifications.}, 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} } @article{TsuprykovAndoReichetzederetal.2016, author = {Tsuprykov, Oleg and Ando, Ryotaro and Reichetzeder, Christoph and von Websky, Karoline and Antonenko, Viktoriia and Sharkovska, Yuliya and Chaykovska, Lyubov and Rahnenfuehrer, Jan and Hasan, Ahmed Abdallah Abdalrahman Mohamed and Tammen, Harald and Alter, Markus L. and Klein, Thomas and Ueda, Seiji and Yamagishi, Sho-ichi and Okuda, Seiya and Hocher, Berthold}, title = {The dipeptidyl peptidase inhibitor linagliptin and the angiotensin II receptor blocker telmisartan show renal benefit by different pathways in rats with 5/6 nephrectomy}, series = {Kidney international : official journal of the International Society of Nephrology}, volume = {89}, journal = {Kidney international : official journal of the International Society of Nephrology}, publisher = {Nature Publ. Group}, address = {New York}, issn = {0085-2538}, doi = {10.1016/j.kint.2016.01.016}, pages = {1049 -- 1061}, year = {2016}, abstract = {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/).}, 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{HocherHeidenvonWebskyetal.2011, author = {Hocher, Berthold and Heiden, Susi and von Websky, Karoline and Arafat, Ayman M. and Rahnenf{\"u}hrer, Jan and Alter, Markus L. and Kalk, Philipp and Ziegler, Dieter and Fischer, Yvan and Pfab, Thiemo}, title = {Renal effects of the novel selective adenosine A(1) receptor blocker SLV329 in experimental liver cirrhosis in rats}, series = {PLoS one}, volume = {6}, journal = {PLoS one}, number = {3}, publisher = {PLoS}, address = {San Fransisco}, issn = {1932-6203}, doi = {10.1371/journal.pone.0017891}, pages = {8}, year = {2011}, abstract = {Liver cirrhosis is often complicated by an impaired renal excretion of water and sodium. Diuretics tend to further deteriorate renal function. It is unknown whether chronic selective adenosine A(1) receptor blockade, via inhibition of the hepatorenal reflex and the tubuloglomerular feedback, might exert diuretic and natriuretic effects without a reduction of the glomerular filtration rate. In healthy animals intravenous treatment with the novel A(1) receptor antagonist SLV329 resulted in a strong dose-dependent diuretic (up to 3.4-fold) and natriuretic (up to 13.5-fold) effect without affecting creatinine clearance. Male Wistar rats with thioacetamide-induced liver cirrhosis received SLV329, vehicle or furosemide for 12 weeks. The creatinine clearance of cirrhotic animals decreased significantly (-36.5\%, p < 0.05), especially in those receiving furosemide (-41.9\%, p < 0.01). SLV329 was able to prevent this decline of creatinine clearance. Mortality was significantly lower in cirrhotic animals treated with SLV329 in comparison to animals treated with furosemide (17\% vs. 54\%, p < 0.05). SLV329 did not relevantly influence the degree of liver fibrosis, kidney histology or expression of hepatic or renal adenosine receptors. In conclusion, chronic treatment with SLV329 prevented the decrease of creatinine clearance in a rat model of liver cirrhosis. Further studies will have to establish whether adenosine A(1) receptor antagonists are clinically beneficial at different stages of liver cirrhosis.}, language = {en} } @article{DschietzigKrauseRelleHennequinetal.2015, author = {Dschietzig, Thomas Bernd and Krause-Relle, Katharina and Hennequin, Maud and von Websky, Karoline and Rahnenfuhrer, Jan and Ruppert, Jana and Groena, Hans Juergen and Armbruster, Franz Paul and Bathgate, Ross A. D. and Aschenbach, Joerg R. and Forssmann, Wolf-Georg and Hocher, Berthold}, title = {Relaxin-2 does not Ameliorate Nephropathy in an experimental model of Type-1 Diabetes}, series = {Kidney \& blood pressure research : official organ of the Gesellschaft f{\"u}r Nephrologie}, volume = {40}, journal = {Kidney \& blood pressure research : official organ of the Gesellschaft f{\"u}r Nephrologie}, number = {1}, publisher = {Karger}, address = {Basel}, issn = {1420-4096}, doi = {10.1159/000368484}, pages = {77 -- 88}, year = {2015}, abstract = {Background/Aims: In diabetic nephropathy (DN), the current angiotensin-II-blocking pharmacotherapy is frequently failing. For diabetic cardiomyopathy (DC), there is no specific remedy available. Relaxin-2 (Rlx) - an anti-fibrotic, anti-inflammatory, and vasoprotecting peptide - is a candidate drug for both. Methods: Low-dose (32 mu g/kg/day) and high-dose (320 mu g/kg/day) Rlx were tested against vehicle (n = 20 each) and non-diabetic controls (n = 14) for 12 weeks in a model of type-1 diabetes induced in endothelial nitric oxide synthase knock-out (eNOS-KO) mice by intraperitoneal injection of streptozotocin. Results: Diabetic animals showed normal plasma creatinine, markedly increased albuminuria and urinary malonyldialdehyde, elevated relative kidney weight, glomerulosclerosis, and increased glomerular size, but no relevant interstitial fibrosis. Neither dose of Rlx affected these changes although the drug was active and targeted plasma levels were achieved. Of note, we found no activation of the renal TGF-beta pathway in this model. In the hearts of diabetic animals, no fibrotic alterations indicative of DC could be determined which precluded testing of the initial hypothesis. Conclusions: We investigated a model showing early DN without overt tubulo-interstitial fibrosis and activation of the TGF-beta-Smad-2/3 pathway. In this model, Rlx proved ineffective; however, the same may not apply to other models and types of diabetes.}, 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} } @article{HasanvonWebskyReichetzederetal.2019, author = {Hasan, Ahmed Abdallah Abdalrahman Mohamed and von Websky, Karoline and Reichetzeder, Christoph and Tsuprykov, Oleg and Gaballa, Mohamed Mahmoud Salem Ahmed and Guo, Jingli and Zeng, Shufei and Delic, Denis and Tammen, Harald and Klein, Thomas and Kleuser, Burkhard and Hocher, Berthold}, title = {Mechanisms of GLP-1 receptor-independent renoprotective effects of the dipeptidyl peptidase type 4 inhibitor linagliptin in GLP-1 receptor knockout mice with 5/6 nephrectomy}, series = {Kidney international : official journal of the International Society of Nephrology}, volume = {95}, journal = {Kidney international : official journal of the International Society of Nephrology}, number = {6}, publisher = {Elsevier}, address = {New York}, issn = {0085-2538}, doi = {10.1016/j.kint.2019.01.010}, pages = {1373 -- 1388}, year = {2019}, abstract = {Dipeptidyl peptidase type 4 (DPP-4) inhibitors were reported to have beneficial effects in experimental models of chronic kidney disease. The underlying mechanisms are not completely understood. However, these effects could be mediated via the glucagon-like peptide-1 (GLP-1)/GLP-1 receptor (GLP1R) pathway. Here we investigated the renal effects of the DPP-4 inhibitor linagliptin in Glp1r-/- knock out and wild-type mice with 5/6 nephrectomy (5/6Nx). Mice were allocated to groups: sham + wild type + placebo; 5/6Nx+ wild type + placebo; 5/6Nx+ wild type + linagliptin; sham + knock out+ placebo; 5/6Nx + knock out+ placebo; 5/6Nx + knock out+ linagliptin. 5/6Nx caused the development of renal interstitial fibrosis, significantly increased plasma cystatin C and creatinine levels and suppressed renal gelatinase/collagenase, matrix metalloproteinase-1 and -13 activities; effects counteracted by linagliptin treatment in wildtype and Glp1r-/- mice. Two hundred ninety-eight proteomics signals were differentially regulated in kidneys among the groups, with 150 signals specific to linagliptin treatment as shown by mass spectrometry. Treatment significantly upregulated three peptides derived from collagen alpha-1(I), thymosin beta 4 and heterogeneous nuclear ribonucleoprotein Al (HNRNPA1) and significantly downregulated one peptide derived from Y box binding protein-1 (YB-1). The proteomics results were further confirmed using western blot and immunofluorescence microscopy. Also, 5/6Nx led to significant up-regulation of renal transforming growth factor-beta 1 and pSMAD3 expression in wild type mice and linagliptin significantly counteracted this up-regulation in wild type and GIplr-/- mice. Thus, the renoprotective effects of linagliptin cannot solely be attributed to the GLP-1/GLP1R pathway, highlighting the importance of other signaling pathways (collagen I homeostasis, HNRNPA1,YB-1,thymosin beta 4 and TGF-beta 1) influenced by DPP-4 inhibition.}, language = {en} } @article{LuZengChenetal.2013, author = {Lu, Yong-Ping and Zeng, De-Ying and Chen, You-Peng and Liang, Xu-Jing and Xu, Jie-Ping and Huang, Si-Min and Lai, Zhi-Wei and Wen, Wang-Rong and von Websky, Karoline and Hocher, Berthold}, title = {Low birth weight is associated with lower respiratory tract infections in children with hand, foot, and mouth disease}, series = {Clinical laboratory : the peer reviewed journal for clinical laboratories and laboratories related to blood transfusion}, volume = {59}, journal = {Clinical laboratory : the peer reviewed journal for clinical laboratories and laboratories related to blood transfusion}, number = {9-10}, publisher = {Clin Lab Publ., Verl. Klinisches Labor}, address = {Heidelberg}, issn = {1433-6510}, doi = {10.7754/Clin.Lab.2012.120725}, pages = {985 -- 992}, year = {2013}, abstract = {Background: Low birth weight (LBW) might be a risk factor for acquiring lower respiratory tract infections (LRTIs) associated with disease related complications in early childhood. HFMD, a frequent viral infection in southern China, is a leading cause of lower respiratory tract infections in children. We analyzed whether LBW is a risk factor for children with HFMD to develop lower respiratory tract infections. Methods: A total of 298 children with HFMD, admitted to a hospital in Qingyuan city, Guangdong province, were recruited. Demographic data and clinical parameters such as serum glucose level and inflammatory markers including peripheral white blood cell count, serum C-reactive protein, and erythrocyte sedimentation rate were routinely collected on admission. Birth weight data were derived from birth records. Results: Mean birth weight (BW) was 167 g lower in patients with HFMD and LRTIs as compared to patients with solely HFMD (p = 0.022) and the frequency of birth weight below the tenth percentile was significantly higher in patients with HFMD and LRTIs (p = 0.002). Conclusions: The results of the study show that low birth weight is associated with a higher incidence of lower respiratory tract infections in young children with HFMD.}, language = {en} } @inproceedings{HocherTsuprykovAlteretal.2013, author = {Hocher, Berthold and Tsuprykov, Oleg and Alter, Markus L. and von Websky, Karoline and Chaykovska, Lyubov and Antonenko, V. and Rahnenf{\"u}hrer, Jan and Klein, T. and Reichetzeder, Christoph}, title = {Linagliptin and the angiotensin II receptor blocker telmisartan show comparable efficacy but different renoprotective pathways in rats with 5/6 nephrectomy}, series = {Diabetologia : journal of the European Association for the Study of Diabetes (EASD)}, volume = {56}, booktitle = {Diabetologia : journal of the European Association for the Study of Diabetes (EASD)}, number = {15-16}, publisher = {Springer}, address = {New York}, issn = {0012-186X}, pages = {S66 -- S66}, year = {2013}, language = {en} }