Get access

An in vitro scanning microradiography study of the reduction in hydroxyapatite demineralization rate by statherin-like peptides as a function of increasing N-terminal length

Authors

  • Saleha Shah,

    1. Centre for Oral Growth and Development, Barts and The London School of Medicine and Dentistry, Queen Mary, University of London, London, UK
    Search for more papers by this author
  • Jelena Kosoric,

    1. Centre for Oral Growth and Development, Barts and The London School of Medicine and Dentistry, Queen Mary, University of London, London, UK
    Search for more papers by this author
  • Mark P. Hector,

    1. Centre for Oral Growth and Development, Barts and The London School of Medicine and Dentistry, Queen Mary, University of London, London, UK
    Search for more papers by this author
  • Paul Anderson

    1. Centre for Oral Growth and Development, Barts and The London School of Medicine and Dentistry, Queen Mary, University of London, London, UK
    Search for more papers by this author

Dr Paul Anderson, Francis Bancroft Building, QMUL, Mile End Road, London E1 4NS, UK

Telefax: +44–207–8827089
E-mail: p.anderson@qmul.ac.uk

Abstract

Shah S, Kosoric J, Hector MP, Anderson P. An in vitro scanning microradiography study of the reduction in hydroxyapatite demineralization rate by statherin-like peptides as a function of increasing N-terminal length.
Eur J Oral Sci 2011; 119 (Suppl. 1): 13–18. © 2011 Eur J Oral Sci

Enamel demineralization is slowed by salivary proteins that inhibit calcium hydroxyapatite (HA) demineralization. Statherin (StN43), a 43-residue phosphorylated salivary protein with primary sequence similarities to osteopontin and caseins, binds calcium and HA. The aim of this study was to identify the minimum length of the functional domain of the statherin molecule required for cariostatic function by measuring the efficacy of peptides of progressively shorter length (i.e. containing only the N-terminal 21 (StN21), 15 (StN15), 10 (StN10), or 5 (StN5) residues) to reduce HA demineralization rates (RDHA). Porous HA blocks were used as enamel analogues, and were exposed to 0.1 M acetic acid at pH 4 for 120 h, rinsed, and treated with StN21, StN15, StN10, or StN5 peptides (1.88 × 10−5 M) for 24 h, then demineralized for a further 120 h. The RDHA was measured, before and after peptide treatment, using scanning microradiography. Hydroxyapatite blocks treated with StN21 and StN15 demonstrated a 50–60% reduction in the RDHA. However, no reduction in the RDHA was observed following treatment with either StN10, StN5, or buffer only. The mechanism by which statherin-like peptides reduce RDHA may be associated with their binding to HA surfaces. Comparisons with previously published binding energies of statherin to HA also suggest that statherin-like peptides containing 15 N-terminal residues or more, are required for binding, suggesting a link between binding and demineralization reduction.

Ancillary