@article{BrandenburgKramannKoosetal.2013, author = {Brandenburg, Vincent M. and Kramann, Rafael and Koos, Ralf and Krueger, Thilo and Schurgers, Leon and M{\"u}hlenbruch, Georg and H{\"u}bner, Sinah and Gladziwa, Ulrich and Drechler, Christiane and Ketteler, Markus}, title = {Relationship between sclerostin and cardiovascular calcification in hemodialysis patients: a cross-sectional study}, series = {BMC Nephrology}, volume = {14}, journal = {BMC Nephrology}, number = {219}, issn = {1471-2369}, doi = {10.1186/1471-2369-14-219}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-122070}, year = {2013}, abstract = {Background: Sclerostin is a Wnt pathway antagonist regulating osteoblast activity and bone turnover. Here, we assessed the potential association of sclerostin with the development of coronary artery (CAC) and aortic valve calcifications (AVC) in haemodialysis (HD) patients. Methods: We conducted a cross-sectional multi-slice computed tomography (MS-CT) scanning study in 67 chronic HD patients (59.4 +/- 14.8 yrs) for measurement of CAC and AVC. We tested established biomarkers as well as serum sclerostin (ELISA) regarding their association to the presence of calcification. Fifty-four adults without relevant renal disease served as controls for serum sclerostin levels. Additionally, sclerostin expression in explanted aortic valves from 15 dialysis patients was analysed ex vivo by immunohistochemistry and mRNA quantification (Qt-RT-PCR). Results: CAC (Agatston score > 100) and any AVC were present in 65\% and in 40\% of the MS-CT patient group, respectively. Serum sclerostin levels (1.53 +/- 0.81 vs 0.76 +/- 0.31 ng/mL, p < 0.001) were significantly elevated in HD compared to controls and more so in HD patients with AVC versus those without AVC (1.78 +/- 0.84 vs 1.35 +/- 0.73 ng/mL, p = 0.02). Multivariable regression analysis for AVC revealed significant associations with higher serum sclerostin. Ex vivo analysis of uraemic calcified aortic valves (n = 10) revealed a strong sclerostin expression very close to calcified regions (no sclerostin staining in non-calcified valves). Correspondingly, we observed a highly significant upregulation of sclerostin mRNA in calcified valves compared to non-calcified control valves. Conclusion: We found a strong association of sclerostin with calcifying aortic heart valve disease in haemodialysis patients. Sclerostin is locally produced in aortic valve tissue adjacent to areas of calcification.}, language = {en} } @article{SchneiderSchneiderKrieteretal.2015, author = {Schneider, Andreas and Schneider, Markus P. and Krieter, Detlef H. and Genser, Bernd and Scharnagl, Hubert and Stojakovic, Tatjana and Wanner, Christoph and Drechsler, Christiane}, title = {Effect of high-flux dialysis on circulating FGF-23 levels in end-stage renal disease patients: results from a randomized trial}, series = {PLoS ONE}, volume = {10}, journal = {PLoS ONE}, number = {5}, doi = {10.1371/journal.pone.0128079}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-148559}, pages = {e0128079}, year = {2015}, abstract = {Background In patients undergoing maintenance hemodialysis (HD), increased levels of circulating fibroblast growth factor-23 (FGF-23) are independently associated with cardiovascular events and mortality. Interventional strategies aiming to reduce levels of FGF-23 in HD patients are of particular interest. The purpose of the current study was to compare the impact of high-flux versus low-flux HD on circulating FGF-23 levels. Methods We conducted a post-hoc analysis of the MINOXIS study, including 127 dialysis patients randomized to low-flux (n = 62) and high-flux (n = 65) HD for 52 weeks. Patients with valid measures for FGF-23 investigated baseline and after 52 weeks were included. Results Compared to baseline, a significant increase in FGF-23 levels after one year of low-flux HD was observed (Delta plasma FGF-23: +4026 RU/ml; p < 0.001). In contrast, FGF-23 levels remained stable in the high flux group (Delta plasma FGF-23: +373 RU/ml, p = 0.70). The adjusted difference of the absolute change in FGF-23 levels between the two treatment groups was statistically significant (p < 0.01). Conclusions Over a period of 12 months, high-flux HD was associated with stable FGF-23 levels, whereas the low-flux HD group showed an increase of FGF-23. However, the implications of the different FGF 23 time-trends in patients on high flux dialysis, as compared to the control group, remain to be explored in specifically designed clinical trials.}, language = {en} }