Association between low bone mineral density and increased α-defensin in salivary fluid among postmenopausal women.

OBJECTIVE

This study aims to evaluate the concentration of α-defensin human neutrophil peptide-1 (HNP-1; a peptide released by neutrophils) in salivary fluid among postmenopausal women and to compare bone mineral density among postmenopausal women with different concentrations of this peptide.

METHODS

We consecutively enrolled 61 postmenopausal women. Bone density was measured by dual-energy x-ray absorptiometry, and α-defensin HNP-1 was identified by proteomic analysis of salivary fluid specimen.

RESULTS

We found a significant difference in bone mineral density among postmenopausal women with different concentrations of α-defensin HNP-1 in salivary fluid. In particular, women with higher α-defensin concentrations had the lowest bone density in comparison with those with a lower concentration of defensin (P = 0.03 between groups). Univariate and multivariate linear regression analyses showed a significative inverse relationship between bone mineral density and age (r = -0.58, β = -0.56) and peak of α-defensin (r = -0.26, β = -0.21).

CONCLUSIONS

Low bone mineral density is found in postmenopausal women with high α-defensin HNP-1 concentrations. Therefore, α-defensin HNP-1 could be a novel biomarker for osteoporosis.