Hydroxyapatite coating affects the Wnt signaling pathway during peri-implant healing in vivo

A Thorfve; C Lindahl; W Xia; K Igawa; A Lindahl; P Thomsen; A Palmquist; P Tengvall

doi:10.1016/j.actbio.2013.12.012

Hydroxyapatite coating affects the Wnt signaling pathway during peri-implant healing in vivo

Acta Biomater. 2014 Mar;10(3):1451-62. doi: 10.1016/j.actbio.2013.12.012. Epub 2013 Dec 14.

Authors

A Thorfve¹, C Lindahl², W Xia², K Igawa³, A Lindahl⁴, P Thomsen⁵, A Palmquist⁵, P Tengvall⁵

Affiliations

¹ Department of Biomaterials, Institute of Clinical Sciences, The Sahlgrenska Academy, University of Gothenburg, Box 412, SE-405 30 Gothenburg, Sweden; BIOMATCELL VINN Excellence Center of Biomaterials and Cell Therapy, The Sahlgrenska Academy at University of Gothenburg, Box 412, SE-405 30 Gothenburg, Sweden. Electronic address: anna.thorfve@biomaterials.gu.se.
² BIOMATCELL VINN Excellence Center of Biomaterials and Cell Therapy, The Sahlgrenska Academy at University of Gothenburg, Box 412, SE-405 30 Gothenburg, Sweden; Department of Engineering Sciences, Angstrom Laboratory, Uppsala University, Box 534, SE-751 21 Uppsala, Sweden.
³ BIOMATCELL VINN Excellence Center of Biomaterials and Cell Therapy, The Sahlgrenska Academy at University of Gothenburg, Box 412, SE-405 30 Gothenburg, Sweden; Department of Oral and Maxillofacial Surgery, Southern Tohoku Research Institute for Neuroscience, Southern Tohoku General Hospital, 71-15 Yatsuyamada Koriyama, Fukushima 9638-563, Japan.
⁴ BIOMATCELL VINN Excellence Center of Biomaterials and Cell Therapy, The Sahlgrenska Academy at University of Gothenburg, Box 412, SE-405 30 Gothenburg, Sweden; Department of Clinical Chemistry and Transfusion Medicine, The Sahlgrenska Academy, University of Gothenburg, Bruna Straket 16, SE-413 45 Gothenburg, Sweden.
⁵ Department of Biomaterials, Institute of Clinical Sciences, The Sahlgrenska Academy, University of Gothenburg, Box 412, SE-405 30 Gothenburg, Sweden; BIOMATCELL VINN Excellence Center of Biomaterials and Cell Therapy, The Sahlgrenska Academy at University of Gothenburg, Box 412, SE-405 30 Gothenburg, Sweden.

PMID: 24342040
DOI: 10.1016/j.actbio.2013.12.012

Abstract

Owing to its bio- and osteoconductivity, hydroxyapatite (HA) is a widely used implant material, but its osteogenic properties are only partly evaluated in vitro and in vivo. The present study focused on bone healing adjacent to HA-coated titanium (Ti) implants, with or without incorporated lithium ions (Li(+)). Special attention was given to the Wnt signaling pathway. The implants were inserted into rat tibia for 7 or 28 days and analyzed ex vivo, mainly by histomorphometry and quantitative real-time polymerase chain reaction (qPCR). HA-coated implants showed, irrespective of Li(+) content, bone-implant contact (BIC) and removal torque values significantly higher than those of reference Ti. Further, the expression of OCN, CTSK, COL1A1, LRP5/6 and WISP1 was significantly higher in implant-adherent cells of HA-coated implants, with or without Li(+). Significantly higher β-catenin expression and significantly lower COL2A1 expression were observed in peri-implant bone cells from HA with 14 ng cm(-2) released Li(+). Interestingly, Ti implants showed a significantly larger bone area (BA) in the threads than HA with 39 ng cm(-2) released Li(+), but had a lower BIC than any HA-coated implant. This study shows that HA, with or without Li(+), is a strong activator of the Wnt signaling pathway, and may to some degree explain its high bone induction capacity.

Keywords: Gene expression; Hydroxyapatite; Lithium; Osseointegration; Wnt signaling pathway.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Bone and Bones / drug effects
Bone and Bones / ultrastructure
Cell Adhesion / drug effects
Cell Adhesion / genetics
Coated Materials, Biocompatible / pharmacology*
Durapatite / pharmacology*
Enzyme-Linked Immunosorbent Assay
Gene Expression Regulation / drug effects
Immunohistochemistry
Implants, Experimental*
Male
Rats, Sprague-Dawley
Torque
Wnt Signaling Pathway / drug effects*
Wnt Signaling Pathway / genetics
Wound Healing / drug effects*
beta Catenin / metabolism

Substances

Coated Materials, Biocompatible
beta Catenin
Durapatite