VDR deficiency affects alveolar bone and cementum apposition in mice

Arch Oral Biol. 2011 Jul;56(7):672-7. doi: 10.1016/j.archoralbio.2010.12.004. Epub 2010 Dec 24.

Abstract

Objective: To compare the mineralisation density (MD), morphology and histology of alveolar bone and cementum amongst VDR +/+, VDR -/-, and VDR -/- groups supplemented with a diet TD 96348, containing 20% lactose, 2.0% calcium and 1.25% phosphorous.

Methods: Four groups of mice (6 mice/group) were identified by genotyping: VDR +/+ mice (VDR wild type), VDR -/- mice (VDR deficient), VDR -/- offsprings derived from VDR -/- parents receiving a supplemental diet (early rescued), and VDR -/- mice fed with a supplemental diet beginning at age one month (late rescued). All mice were sacrificed at age 70.5 days. Micro-CT was used to compare MD and morphology of alveolar bone and cementum. H-E and Toluidine blue staining was used to examine the ultrastructure of the alveolar bone and cementum at matched locations.

Results: In VDR -/- group, alveolar bone and cementum failed to mineralise normally. Early rescue increased MD of alveolar bone in VDR -/- mice with excessive alveolar bone formation, but which not observed in late rescue group. MD and morphology of cementum-dentine complex in both early and late rescue groups were comparable with VDR +/+ group when feeding with high-calcium rescue diet.

Conclusions: VDR affects alveolar bone mineralisation and formation systemically and locally. However, cementum apposition and mineralisation is mainly regulated by calcium concentrations in serum.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Age Factors
  • Alveolar Process / physiopathology*
  • Alveolar Process / ultrastructure
  • Animals
  • Bone Density / physiology
  • Calcification, Physiologic / physiology
  • Calcium, Dietary / therapeutic use
  • Cementogenesis / physiology*
  • Coloring Agents
  • Dental Cementum / physiopathology
  • Dental Cementum / ultrastructure
  • Dental Pulp Cavity / pathology
  • Dental Pulp Cavity / physiopathology
  • Dentin / pathology
  • Dentin / physiopathology
  • Dentinogenesis / physiology
  • Dietary Supplements
  • Female
  • Lactose / therapeutic use
  • Male
  • Mandible / pathology
  • Mandible / physiopathology
  • Mice
  • Mice, Knockout
  • Molar / pathology
  • Molar / physiopathology
  • Osteogenesis / physiology*
  • Osteoporosis / pathology
  • Osteoporosis / physiopathology
  • Phosphorus, Dietary / therapeutic use
  • Receptors, Calcitriol / deficiency*
  • Receptors, Calcitriol / physiology
  • Tolonium Chloride
  • Tooth Calcification / physiology
  • X-Ray Microtomography

Substances

  • Calcium, Dietary
  • Coloring Agents
  • Phosphorus, Dietary
  • Receptors, Calcitriol
  • Tolonium Chloride
  • Lactose