Naunyn-Schmiedeberg's Archives of Pharmacology

, Volume 390, Issue 9, pp 939–948 | Cite as

Differences in the renal antifibrotic cGMP/cGKI-dependent signaling of serelaxin, zaprinast, and their combination

  • Veronika Wetzl
  • Elisabeth Schinner
  • Frieder Kees
  • Lothar Faerber
  • Jens SchlossmannEmail author
Original Article


Renal fibrosis is an important factor for end-stage renal failure. However, only few therapeutic options for its treatment are established. Zaprinast, a phosphodiesterase 5 inhibitor, and serelaxin, the recombinant form of the naturally occurring hormone relaxin, are differently acting modulators of cyclic guanosine monophosphate (cGMP) signaling. Both agents enhance cGMP availability in kidney tissue. These substances alone or in combination might interfere with the development of kidney fibrosis. Therefore, we compared the effects of combination therapy with the effects of monotherapy on renal fibrosis. Renal fibrosis was induced by unilateral ureteral obstruction (UUO) for 7 days in wild-type (WT) and cGKI knockout (KO) mice. Renal antifibrotic effects were assessed after 7 days. In WT, zaprinast and the combination of zaprinast and serelaxin significantly reduced renal interstitial fibrosis assessed by α-SMA, fibronectin, collagen1A1, and gelatinases (MMP2 and MMP9). Intriguingly in cGKI-KO, mRNA and protein expression of fibronectin and collagen1A1 were reduced by zaprinast, in contrast to serelaxin. Gelatinases are not regulated by zaprinast. Although both substances showed similar antifibrotic properties in WT, they distinguished in their effect mechanisms. In contrast to serelaxin which acts both on Smad2 and Erk1, zaprinast did not significantly diminish Erk1/2 phosphorylation. Interestingly, the combination of serelaxin/zaprinast achieved no additive antifibrotic effects compared to the monotherapy. Due to antifibrotic effects of zaprinast in cGKI-KO, we hypothesize that additional cGKI-independent mechanisms are supposed for antifibrotic signaling of zaprinast.


Phosphodiesterase 5 inhibitor Serelaxin cGMP-dependent protein kinase Kidney Interstitial fibrosis Signaling 



We thank Astrid Seefeld and Gertraud Wilberg for their excellent technical assistance.

Compliance with ethical standards


This work was financially supported by Novartis Pharma GmbH and the Bavarian State and Sonderforschungsbereich SFB699.

Conflict of interest

PhD thesis of Veronika Wetzl is funded by Novartis Pharma GmbH. Veronika Wetzl and Lothar Faerber are employees at Novartis Pharma GmbH. Other authors declare that they have no conflict of interest.

Ethical approval

All applicable international, national, and/or institutional guidelines for the care and use of animals were followed.


  1. Bathgate RA, Halls ML, van der Westhuizen ET, Callander GE, Kocan M, Summers RJ (2013) Relaxin family peptides and their receptors. Physiol Rev 93:405–480. doi: 10.1152/physrev.00001.2012 CrossRefPubMedGoogle Scholar
  2. Bender AT, Beavo JA (2006) Cyclic nucleotide phosphodiesterases: molecular regulation to clinical use. Pharmacol Rev 58:488–520. doi: 10.1124/pr.58.3.5 CrossRefPubMedGoogle Scholar
  3. Buglioni A, Burnett JC Jr (2016) New pharmacological strategies to increase cGMP. Annu Rev Med 67:229–243. doi: 10.1146/annurev-med-052914-091923 CrossRefPubMedGoogle Scholar
  4. Chen Y, Blom IE, Sa S, Goldschmeding R, Abraham DJ, Leask A (2002) CTGF expression in mesangial cells: involvement of SMADs MAP kinase, and PKC. Kidney Int 62:1149–1159. doi: 10.1111/j.1523-1755.2002.kid567.x CrossRefPubMedGoogle Scholar
  5. Chevalier RL, Forbes MS, Thornhill BA (2009) Ureteral obstruction as a model of renal interstitial fibrosis and obstructive nephropathy. Kidney Int 75:1145–1152. doi: 10.1038/ki.2009.86 CrossRefPubMedGoogle Scholar
  6. Chow BS, Chew EG, Zhao C, Bathgate RA, Hewitson TD, Samuel CS (2012) Relaxin signals through a RXFP1-pERK-nNOS-NO-cGMP-dependent pathway to up-regulate matrix metalloproteinases: the additional involvement of iNOS. PLoSOne 7:e42714. doi: 10.1371/journal.pone.0042714 CrossRefGoogle Scholar
  7. Cui W et al (2014) Increasing cGMP-dependent protein kinase activity attenuates unilateral ureteral obstruction-induced renal fibrosis. Am J Physiol Renal Physiol 306:F996–1007. doi: 10.1152/ajprenal.00657.2013 CrossRefPubMedPubMedCentralGoogle Scholar
  8. D'Andrea MR, Qiu Y, Haynes-Johnson D, Bhattacharjee S, Kraft P, Lundeen S (2005) Expression of PDE11A in normal and malignant human tissues. J Histochem Cytochem 53:895–903. doi: 10.1369/jhc.5A6625.2005 CrossRefPubMedGoogle Scholar
  9. Francis SH, Corbin JD (1994) Structure and function of cyclic nucleotide-dependent protein kinases. Annu Rev Physiol 56:237–272. doi: 10.1146/ CrossRefPubMedGoogle Scholar
  10. Francis SH, Turko IV, Corbin JD (2001) Cyclic nucleotide phosphodiesterases: relating structure and function. Prog Nucleic Acid Res Mol Biol 65:1–52PubMedGoogle Scholar
  11. Giannandrea M, Parks WC (2014) Diverse functions of matrix metalloproteinases during fibrosis. Dis Model Mech 7:193–203. doi: 10.1242/dmm.012062 CrossRefPubMedPubMedCentralGoogle Scholar
  12. Guan Z, Miller SB, Greenwald JE (1995) Zaprinast accelerates recovery from established acute renal failure in the rat. Kidney Int 47:1569–1575. doi: 10.1038/ki.1995.220 CrossRefPubMedGoogle Scholar
  13. Halls ML, Bathgate RA, Sutton SW, Dschietzig TB, Summers RJ (2015) International Union of Basic and Clinical Pharmacology. XCV. Recent advances in the understanding of the pharmacology and biological roles of relaxin family peptide receptors 1-4, the receptors for relaxin family peptides. Pharmacol Rev 67:389–440. doi: 10.1124/pr.114.009472 CrossRefPubMedPubMedCentralGoogle Scholar
  14. Hohenstein B, Daniel C, Wittmann S, Hugo C (2008) PDE-5 inhibition impedes TSP-1 expression, TGF-β activation and matrix accumulation in experimental glomerulonephritis. Nephrology Dialysis Transplantation 23:3427–3436. doi: 10.1093/ndt/gfn319 CrossRefGoogle Scholar
  15. Ibrahim MA, Satoh N, Ueda S (2003) Possible impact of nitric oxide on the antihypertensive effect of captopril and zaprinast. Adv Ther 20:143–148. doi: 10.1007/BF02850201 CrossRefPubMedGoogle Scholar
  16. Kiss T et al (2014) Novel mechanisms of sildenafil in pulmonary hypertension involving cytokines/chemokines MAP kinases and Akt. PLoS One 9:e104890. doi: 10.1371/journal.pone.0104890 CrossRefPubMedPubMedCentralGoogle Scholar
  17. Kulkarni SK, Patil CS (2004) Phosphodiesterase 5 enzyme and its inhibitors: update on pharmacological and therapeutical aspects. Methods Find Exp Clin Pharmacol 26:789–799. doi: 10.1358/mf.2004.26.10.872561 CrossRefPubMedGoogle Scholar
  18. López-De León A, Rojkind M (1985) A simple micromethod for collagen and total protein determination in formalin-fixed paraffin-embedded sections. Journal of Histochemistry & Cytochemistry 33:737–743. doi: 10.1177/33.8.2410480 CrossRefGoogle Scholar
  19. Lowry OH, Rosebrough NJ, Farr AL, Randall RJ (1951) Protein measurement with the Folin phenol reagent. J Biol Chem 193:265–275PubMedGoogle Scholar
  20. Metra M et al (2013) Effect of serelaxin on cardiac, renal, and hepatic biomarkers in the relaxin in acute heart failure (RELAX-AHF) development program: correlation with outcomes. J Am Coll Cardiol 61:196–206. doi: 10.1016/j.jacc.2012.11.005 CrossRefPubMedGoogle Scholar
  21. Neild GH (2016) Life expectancy with chronic kidney disease: an educational review. Pediatr Nephrol:1–6. doi: 10.1007/s00467-016-3383-8
  22. Novartis (2017) provides update on Phase III study of RLX030 (serelaxin) in patients with acute heart failure. Novartis International AG. Accessed 22 March 2017
  23. Samuel CS (2005) Relaxin: antifibrotic properties and effects in models of disease. Clin Med Res 3:241–249. doi: 10.3121/cmr.3.4.241 CrossRefPubMedPubMedCentralGoogle Scholar
  24. Schinner E, Schramm A, Kees F, Hofmann F, Schlossmann J (2013) The cyclic GMP-dependent protein kinase Ialpha suppresses kidney fibrosis. Kidney Int 84:1198–1206. doi: 10.1038/ki.2013.219 CrossRefPubMedGoogle Scholar
  25. Schinner E, Wetzl V, Schlossmann J (2015) Cyclic nucleotide signalling in kidney fibrosis. Int J Mol Sci 16:2320–2351. doi: 10.3390/ijms16022320 CrossRefPubMedPubMedCentralGoogle Scholar
  26. Schlossmann J, Schinner E (2012) cGMP becomes a drug target Naunyn Schmiedebergs. Arch Pharmacol 385:243–252. doi: 10.1007/s00210-012-0730-6 CrossRefGoogle Scholar
  27. Schramm A, Schinner E, Huettner JP, Kees F, Tauber P, Hofmann F, Schlossmann J (2014) Function of cGMP-dependent protein kinase II in volume load-induced diuresis. Pflugers Arch 466:2009–2018. doi: 10.1007/s00424-014-1445-y CrossRefPubMedGoogle Scholar
  28. Soderling SH, Bayuga SJ, Beavo JA (1998) Identification and characterization of a novel family of cyclic nucleotide phosphodiesterases. J Biol Chem 273:15553–15558. doi: 10.1074/jbc.273.25.15553 CrossRefPubMedGoogle Scholar
  29. Sun XZ, Li ZF, Liu Y, Fang P, Li MX (2010) Inhibition of cGMP phosphodiesterase 5 suppresses matrix metalloproteinase-2 production in pulmonary artery smooth muscles cells. Clin Exp Pharmacol Physiol 37:362–367. doi: 10.1111/j.1440-1681.2009.05304.x CrossRefPubMedGoogle Scholar
  30. Takimoto E et al (2005) Chronic inhibition of cyclic GMP phosphodiesterase 5A prevents and reverses cardiac hypertrophy. Nat Med 11:214–222. doi: 10.1038/nm1175 CrossRefPubMedGoogle Scholar
  31. Teerlink JR et al (2013) Serelaxin, recombinant human relaxin-2, for treatment of acute heart failure (RELAX-AHF): a randomised, placebo-controlled trial. Lancet 381:29–39. doi: 10.1016/S0140-6736(12)61855-8 CrossRefPubMedGoogle Scholar
  32. Wang Y et al (2006) Enhancing cGMP in experimental progressive renal fibrosis: soluble guanylate cyclase stimulation vs. phosphodiesterase inhibition. Am J Physiol Renal Physiol 290:F167–F176. doi: 10.1152/ajprenal.00197.2005 CrossRefPubMedGoogle Scholar
  33. Wang X, Ward CJ, Harris PC, Torres VE (2010) Cyclic nucleotide signaling in polycystic kidney disease. Kidney Int 77:129–140. doi: 10.1038/ki.2009.438 CrossRefPubMedGoogle Scholar
  34. Weber S et al (2007) Rescue of cGMP kinase I knockout mice by smooth muscle specific expression of either isozyme. Circ Res 101:1096–1103. doi: 10.1161/CIRCRESAHA.107.154351 CrossRefPubMedGoogle Scholar
  35. Wetzl V, Schinner E, Kees F, Hofmann F, Faerber L, Schlossmann J (2016) Involvement of cyclic guanosine monophosphate-dependent protein kinase I in renal antifibrotic effects of serelaxin. Front Pharmacol 7:195. doi: 10.3389/fphar.2016.00195 CrossRefPubMedPubMedCentralGoogle Scholar
  36. Yu Q, Stamenkovic I (2000) Cell surface-localized matrix metalloproteinase-9 proteolytically activates TGF-beta and promotes tumor invasion and angiogenesis. Genes Dev 14:163–176. doi: 10.1101/gad.14.2.163 PubMedPubMedCentralGoogle Scholar

Copyright information

© Springer-Verlag GmbH Germany 2017

Authors and Affiliations

  1. 1.Department of Pharmacology and ToxicologyUniversity of RegensburgRegensburgGermany
  2. 2.Novartis Pharma GmbHNurembergGermany

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