Details

Autor(en) / Beteiligte

• Foster, B.L.
• Ao, M.
• Salmon, C.R.
• Chavez, M.B.
• Kolli, T.N.
• Tran, A.B.
• Chu, E.Y.
• Kantovitz, K.R.
• Yadav, M.
• Narisawa, S.
• Millán, J.L.
• Nociti, F.H.
• Somerman, M.J.

Titel

Osteopontin regulates dentin and alveolar bone development and mineralization

Ist Teil von

• Bone (New York, N.Y.), 2018-02, Vol.107, p.196-207

Ort / Verlag

United States: Elsevier Inc

Erscheinungsjahr

2018

Quelle

MEDLINE

Beschreibungen/Notizen

• The periodontal complex is essential for tooth attachment and function and includes the mineralized tissues, cementum and alveolar bone, separated by the unmineralized periodontal ligament (PDL). To gain insights into factors regulating cementum-PDL and bone-PDL borders and protecting against ectopic calcification within the PDL, we employed a proteomic approach to analyze PDL tissue from progressive ankylosis knock-out (Ank−/−) mice, featuring reduced PPi, rapid cementogenesis, and excessive acellular cementum. Using this approach, we identified the matrix protein osteopontin (Spp1/OPN) as an elevated factor of interest in Ank−/− mouse molar PDL. We studied the role of OPN in dental and periodontal development and function. During tooth development in wild-type (WT) mice, Spp1 mRNA was transiently expressed by cementoblasts and strongly by alveolar bone osteoblasts. Developmental analysis from 14 to 240days postnatal (dpn) indicated normal histological structures in Spp1−/− comparable to WT control mice. Microcomputed tomography (micro-CT) analysis at 30 and 90dpn revealed significantly increased volumes and tissue mineral densities of Spp1−/− mouse dentin and alveolar bone, while pulp and PDL volumes were decreased and tissue densities were increased. However, acellular cementum growth was unaltered in Spp1−/− mice. Quantitative PCR of periodontal-derived mRNA failed to identify potential local compensators influencing cementum in Spp1−/− vs. WT mice at 26dpn. We genetically deleted Spp1 on the Ank−/− mouse background to determine whether increased Spp1/OPN was regulating periodontal tissues when the PDL space is challenged by hypercementosis in Ank−/− mice. Ank−/−; Spp1−/− double deficient mice did not exhibit greater hypercementosis than that in Ank−/− mice. Based on these data, we conclude that OPN has a non-redundant role regulating formation and mineralization of dentin and bone, influences tissue properties of PDL and pulp, but does not control acellular cementum apposition. These findings may inform therapies targeted at controlling soft tissue calcification. •Osteopontin (Spp1/OPN) was identified as increased in periodontal tissues of the Ank-/-mouse model of hypercementosis.•Spp1 is transiently expressed by cementoblasts and strongly expressed by alveolar bone osteoblasts during tooth development.•Spp1 knockout in mice causes increased volumes and densities of dentin and alveolar bone•Acellular cementum growth is unaltered in Spp1-/- mice.•Knock-out of Spp1/OPN on the Ank-/- mouse background does not exacerbate hypercementosis.