| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
Department of Biological Sciences (J.J.), Institute for Complex Engineered Systems (J.J., J.S., P.C.), and Bone Tissue Engineering Center (J.J., D.D, P.C.), Carnegie Mellon University, Pittsburgh, Pennsylvania 15213; and Endocrine Research Unit (C.C.), The Mayo Clinic and Foundation, Rochester, Minnesota 55905
Address all correspondence and requests for reprints to: Phil Campbell, Ph.D., Institute for Complex Engineered Systems, Carnegie Mellon University, 5000 Forbes Avenue, 1201 Hamburg Hall, Pittsburgh, Pennsylvania 15213. E-mail: pcampbel{at}cs.cmu.edu.
Pregnancy-associated plasma protein A (PAPP-A) is an IGF binding protein 4 protease that can function to increase local IGF-I bioavailability. Aside from its assumed role during pregnancy, in vitro and in vivo studies have indicated roles for PAPP-A in IGF-I-mediated wound healing, vascular repair, and bone formation. Because bone morphogenetic protein 2 (BMP-2) is known to up-regulate Igf-I gene expression, we hypothesized that PAPP-A may be involved in BMP-2 mechanisms in bone formation. To test this hypothesis, we quantified gene expression of Papp-A in response to BMP-2 treatment and runt-related transcription factor 2, Osterix, and Igf-I in response to PAPP-A protein treatment in human adult mesenchymal stem cells. Our results demonstrate that BMP-2 directly up-regulated Papp-A gene and protein expression. Purified PAPP-A protein directly up-regulated runt-related transcription factor 2 and Igf-I gene expression but not Osterix. When added in combination with recombinant human BMP-2, PAPP-A increased matrix mineralization in the absence of dexamethasone. PAPP-A further demonstrated an angiogenic effect in the chick chorioallontoic membrane, which implicates a critical developmental role and possible therapeutic potential. Our findings suggest that PAPP-A functions in the formation of mineralized tissues through direct up-regulation of key genes. Furthermore, PAPP-A is involved in the formation of new blood vessels, which is essential for proper bone regeneration.
This article has been cited by other articles:
![]() |
B. S Miller, J. T Bronk, T. Nishiyama, H. Yamagiwa, A. Srivastava, M. E Bolander, and C. A Conover Pregnancy associated plasma protein-A is necessary for expeditious fracture healing in mice J. Endocrinol., March 1, 2007; 192(3): 505 - 513. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. A. Jadlowiec, X. Zhang, J. Li, P. G. Campbell, and C. Sfeir Extracellular Matrix-mediated Signaling by Dentin Phosphophoryn Involves Activation of the Smad Pathway Independent of Bone Morphogenetic Protein J. Biol. Chem., March 3, 2006; 281(9): 5341 - 5347. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Endocrinology | Endocrine Reviews | J. Clin. End. & Metab. |
| Molecular Endocrinology | Recent Prog. Horm. Res. | All Endocrine Journals |