Skip to main content

Advertisement

Log in

Pigment epithelium-derived factor (PEDF) reduced expression and synthesis of SOST/sclerostin in bone explant cultures: implication of PEDF-osteocyte gene regulation in vivo

  • Original Article
  • Published:
Journal of Bone and Mineral Metabolism Aims and scope Submit manuscript

Abstract

Mutations in Serpinf1 gene which encodes pigment epithelium-derived factor (PEDF) lead to osteogenesis imperfecta type VI whose hallmark is defective matrix mineralization. We reported previously that PEDF reduced expression and synthesis of Sost/Sclerostin as well as other osteocytes genes encoding proteins that regulate matrix mineralization [1]. To determine whether PEDF had an effect on osteocyte gene expression in bone, we used bone explant cultures. First, osteocytes were isolated from surgical waste of bone fragments obtained from patients undergoing elective foot surgeries under approved IRB protocol by Penn State College of Medicine IRB committee. Primary osteocytes treated with PEDF reduced expression and synthesis of Sost/Sclerostin and matrix phosphoglycoprotein (MEPE) as well as dentin matrix protein (DMP-1). On the whole, PEDF reduced osteocyte protein synthesis by 50% and by 75% on mRNA levels. For bone explants, following collagenase digestion, bone fragments were incubated in alpha-MEM supplemented with 250 ng/ml of PEDF or BSA. After 7 days of incubation in a medium supplemented with PEDF, analysis of mRNA by PCR and protein by western blotting of encoded osteocyte proteins showed reduced Sclerostin synthesis by 39% and MEPE by 27% when compared to fragments incubated in medium supplemented with BSA. mRNA expression levels of osteocytes in bone fragments treated with PEDF were reduced by 50% for both SOST and MEPE when compared to BSA-treated bone fragments. Taken together, the data indicate that PEDF has an effect on osteocyte gene expression in bone and encourage further studies to examine effect of PEDF on bone formation indices in animal models and its effect on osteocyte gene expression in vivo following PEDF administration.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3

Similar content being viewed by others

References

  1. Li F, Song N, Tombran-Tink J, Niyibizi C (2015) Pigment epithelium derived factor suppresses expression of Sost/sclerostin by osteocytes: implication for its role in bone matrix mineralization. J Cell Physiol 24:1651–1661

    Google Scholar 

  2. Dawson DW, Volpert OV, Gillis P, Crawford SE, Xu H, Benedict W, Bouck NP (1999) Pigment epithelium-derived factor: a potent inhibitor of angiogenesis. Science 285:245–248

    Article  CAS  PubMed  Google Scholar 

  3. Tombran-Tink J, Chader GG, Johnson LV (1991) PEDF: a pigment epithelium-derived factor with potent neuronal differentiative activity. Exp Eye Res 53:411–414

    Article  CAS  PubMed  Google Scholar 

  4. Steele FR, Chader GJ, Johnson LV, Tombran-Tink J (1993) Pigment epithelium-derived factor: neurotrophic activity and identification as a member of the serine protease inhibitor gene family. Proc Natl Acad Sci U S A. 90:1526–1530

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  5. Ho TC, Chen SL, Shih SC, Wu JY, Han WH, Cheng HC, Yang SL, Tsao YP (2010) Pigment epithelium-derived factor is an intrinsic antifibrosis factor targeting hepatic stellate cells. Am J Pathol 177:1798–1811

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  6. Cai J, Jiang WG, Grant MB, Boulton M (2006) Pigment epithelium-derived factor inhibits angiogenesis via regulated intracellular proteolysis of vascular endothelial growth factor receptor 1. J Biol Chem 281:3604–3613

    Article  CAS  PubMed  Google Scholar 

  7. Tombran-Tink J (2010) PEDF in angiogenic eye diseases. Curr Mol Med 10:267–278

    Article  CAS  PubMed  Google Scholar 

  8. Becker J, Semler O, Gilissen C, Li Y, Bolz HJ, Giunta C, Bergmann C, Rohrbach M, Koerber F, Zimmermann K, de Vries P, Wirth B, Schoenau E, Wollnik B, Veltman JA, Hoischen A, Netzer C (2011) Exome sequencing identifies truncating mutations in human SERPINF1 in autosomal-recessive osteogenesis imperfecta. Am J Hum Genet 88:362–371

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  9. Homan EP, Rauch F, Grafe I, Lietman C, Doll JA, Dawson B, Bertin T, Napierala D, Morello R, Gibbs R, White L, Miki R, Cohn DH, Crawford S, Travers R, Glorieux FH, Lee B (2011) Mutations in SERPINF1 cause osteogenesis imperfecta type VI. J Bone Miner Res 26:2798–2803

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  10. Venturi G, Gandini A, Monti E, Dalle Carbonare L, Corradi M, Vincenzi M, Valenti MT, Valli M, Pelilli E, Boner A, Mottes M, Antoniazzi F (2012) Lack of expression of SERPINF1, the gene coding for pigment epithelium-derived factor, causes progressively deforming osteogenesis imperfecta with normal type I collagen. J Bone Miner Res 27:723–728

    Article  CAS  PubMed  Google Scholar 

  11. Li F, Song N, Tombran-Tink J, Niyibizi C (2013) Pigment epithelium-derived factor enhances differentiation and mineral deposition of human mesenchymal stem cells. Stem Cells 31:2714–2723

    Article  CAS  PubMed  Google Scholar 

  12. Gattu AK, Swenson ES, Iwakiri Y, Samuel VT, Troiano N, Berry R, Church CD, Rodeheffer MS, Carpenter TO, Chung C (2013) Determination of mesenchymal stem cell fate by pigment epithelium-derived factor (PEDF) results in increased adiposity and reduced bone mineral content. FASEB J 27:4384–4394

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  13. Belinsky GS, Sreekumar B, Andrejecsk JW, Saltzman WM, Gong J, Herzog RI, Lin S, Horsley V, Carpenter TO, Chung C (2016) Pigment epithelium-derived factor restoration increases bone mass and improves bone plasticity in a model of osteogenesis imperfecta type VI via Wnt3a blockade. FASEB J 30:2837–2848

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  14. Sekiya H, Mikuni-Takagaki Y, Kondoh T, Seto K (1999) Synergistic effect of PTH on the mechanical responses of human alveolar osteocytes. Biochem Biophys Res Commun 264:719–723

    Article  CAS  PubMed  Google Scholar 

  15. Gu G, Nars M, Hentunen TA, Metsikko K, Vaananen HK (2006) Isolated primary osteocytes express functional gap junctions in vitro. Cell Tissue Res 323:263–271

    Article  PubMed  Google Scholar 

  16. Stern AR, Stern MM, Van Dyke ME, Jahn K, Prideaux M, Bonewald LF (2012) Isolation and culture of primary osteocytes from the long bones of skeletally mature and aged mice. Biotechniques 52:361–373

    CAS  PubMed  PubMed Central  Google Scholar 

  17. Abubakar AA, Noordin MM, Azmi TI, Kaka U, Loqman MY (2016) The use of rats and mice as animal models in ex vivo bone growth and development studies. Bone Joint Res 5:610–618

    Article  CAS  PubMed  Google Scholar 

  18. Okubo N, Minami Y, Fujiwara H, Umemura Y, Tsuchiya Y, Shirai T, Oda R, Inokawa H, Kubo T, Yagita K (2013) Prolonged bioluminescence monitoring in mouse ex vivo bone culture revealed persistent circadian rhythms in articular cartilages and growth plates. PLoS One 8:e78306

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  19. Chan ME, Lu XL, Huo B, Baik AD, Chiang V, Guldberg RE, Lu HH, Guo XE (2009) A trabecular bone explant model of osteocyte-osteoblast co-culture for bone mechanobiology. Cell Mol Bioeng 2:405–415

    Article  PubMed  PubMed Central  Google Scholar 

  20. Marino S, Staines KA, Brown G, Howard-Jones RA, Adamczyk M (2016) Models of ex vivo explant cultures: applications in bone research. BoneKEy Rep 5:818

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  21. Li F, Cain J, Tombran-Tink J, Niyibizi C (2018) Pigment epithelium derived factor regulates human Sost/Sclerostin and other osteocyte gene expression via the receptor and induction of Erk/Gsk-3beta/beta-catenin signaling. Biochem Biophy Acta Mol Basis Dis 1864:3449–3458

    Article  CAS  Google Scholar 

  22. Atkins GJ, Rowe PS, Lim HP, Welldon KJ, Ormsby R, Wijenayaka AR, Zelenchuk L, Evdokiou A, Findlay DM (2011) Sclerostin is a locally acting regulator of late-osteoblast/preosteocyte differentiation and regulates mineralization through a MEPE-ASARM-dependent mechanism. J Bone Miner Res 26:1425–1436

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  23. Winkler DG, Sutherland MK, Geoghegan JC, Yu C, Hayes T, Skonier JE, Shpektor D, Jonas M, Kovacevich BR, Staehling-Hampton K, Appleby M, Brunkow ME, Latham JA (2003) Osteocyte control of bone formation via sclerostin, a novel BMP antagonist. EMBO J 22:6267–6276

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  24. Paszty C, Turner CH, Robinson MK (2010) Sclerostin: a gem from the genome leads to bone-building antibodies. J Bone Miner Res 25:1897–1904

    Article  CAS  PubMed  Google Scholar 

  25. Tian X, Jee WS, Li X, Paszty C, Ke HZ (2011) Sclerostin antibody increases bone mass by stimulating bone formation and inhibiting bone resorption in a hindlimb-immobilization rat model. Bone 48:197–201

    Article  CAS  PubMed  Google Scholar 

  26. Lin C, Jiang X, Dai Z, Guo X, Weng T, Wang J, Li Y, Feng G, Gao X, He L (2009) Sclerostin mediates bone response to mechanical unloading through antagonizing Wnt/beta-catenin signaling. J Bone Miner Res 24:1651–1661

    Article  CAS  PubMed  Google Scholar 

  27. Addison WN, Nakano Y, Loisel T, Crine P, McKee MD (2008) MEPE-ASARM peptides control extracellular matrix mineralization by binding to hydroxyapatite: an inhibition regulated by PHEX cleavage of ASARM. J Bone Miner Res 23:1638–1649

    Article  CAS  PubMed  Google Scholar 

  28. Martin A, David V, Laurence JS, Schwarz PM, Lafer EM, Hedge AM, Rowe PS (2008) Degradation of MEPE, DMP1, and release of SIBLING ASARM-peptides (minhibins): ASARM-peptide(s) are directly responsible for defective mineralization in HYP. Endocrinology 149:1757–1772

    Article  CAS  PubMed  Google Scholar 

  29. David V, Martin A, Hedge AM, Rowe PS (2009) Matrix extracellular phosphoglycoprotein (MEPE) is a new bone renal hormone and vascularization modulator. Endocrinology 150:4012–4023

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  30. Lu P, Zhang YQ, Zhang H, Li YF, Wang XY, Xu H, Liu ZW, Li L, Dong HY, Zhang ZM (2016) Pigment epithelium-derived factor (PEDF) improves ischemic cardiac functional reserve through decreasing hypoxic cardiomyocyte contractility through PEDF receptor (PEDF-R). J Am Heart Assoc 5:e003179

    PubMed  PubMed Central  Google Scholar 

  31. Gowen LC, Petersen DN, Mansolf AL, Qi H, Stock JL, Tkalcevic GT, Simmons HA, Crawford DT, Chidsey-Frink KL, Ke HZ, McNeish JD, Brown TA (2003) Targeted disruption of the osteoblast/osteocyte factor 45 gene (OF45) results in increased bone formation and bone mass. J Biol Chem 278:1998–2007

    Article  CAS  PubMed  Google Scholar 

  32. Staines KA, Pollard AS, McGonnell IM, Farquharson C, Pitsillides AA (2013) Cartilage to bone transitions in health and disease. J Endocrinol 219:R1–R12

    Article  CAS  PubMed  PubMed Central  Google Scholar 

Download references

Acknowledgements

This work was supported by NIH R21AR067473. We would like to thank Ananya Das for the assistance in organizing the manuscript.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Christopher Niyibizi.

Ethics declarations

Conflict of interest

The authors have no conflict of interest to declare.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Electronic supplementary material

Below is the link to the electronic supplementary material.

BSA and GAPDH expression

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Li, F., Cain, J.D., Tombran-Tink, J. et al. Pigment epithelium-derived factor (PEDF) reduced expression and synthesis of SOST/sclerostin in bone explant cultures: implication of PEDF-osteocyte gene regulation in vivo. J Bone Miner Metab 37, 773–779 (2019). https://doi.org/10.1007/s00774-018-0982-4

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00774-018-0982-4

Keywords

Navigation