TY - JOUR
T1 - Hydroxyapatite coating affects the Wnt signaling pathway during peri-implant healing in vivo
AU - Thorfve, A.
AU - Lindahl, C.
AU - Xia, W.
AU - Igawa, K.
AU - Lindahl, A.
AU - Thomsen, P.
AU - Palmquist, A.
AU - Tengvall, P.
N1 - Funding Information:
The authors thank Lena Emanuelsson, Birgitta Norlindh and Per Borchardt for excellent technical assistance. The study was supported by the Swedish Research Council (VR grants K20125-2X-094952-53 and 6212-0116-037), ALF/LUA Research grants and the BIOMATCELL VINN Excellence Center of Biomaterials and Cell Therapy, supported by VINNOVA and Region Västra Götaland. The authors also thank the Handlanden Hjalmar Svensson Research Foundation.
PY - 2014/3
Y1 - 2014/3
N2 - 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.
AB - 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.
KW - Gene expression
KW - Hydroxyapatite
KW - Lithium
KW - Osseointegration
KW - Wnt signaling pathway
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U2 - 10.1016/j.actbio.2013.12.012
DO - 10.1016/j.actbio.2013.12.012
M3 - Article
C2 - 24342040
AN - SCOPUS:84895068796
VL - 10
SP - 1451
EP - 1462
JO - Acta Biomaterialia
JF - Acta Biomaterialia
SN - 1742-7061
IS - 3
ER -