25-Hydroxyvitamin D Strongly Correlates to LL-37 in Saliva

Objectives: The oral cavity is a unique environment. During the last years, there has been an increased interest regarding the innate immunity of the mouth and especially of the mechanisms by which vitamin D impacts oral health. The interest of researchers has recently been focused on the relationship between vitamin D and the antimicrobial peptide LL-37 as recent studies have shown that the gene CAMP, that encodes the peptide LL-37, is a direct target of both vitamin D and its receptor (Vitamin D Receptor, VDR). The present study aimed toinvestigate the correlation between the 25-Hydroxyvitamin D levels and the concentration of the LL-37 peptide in serum and saliva, so as to determine the possible implications of hypovitaminosis D in the concentration of LL-37 in circulation or topically in the oral cavity.
Methods: Serum and whole saliva levels were obtained from 72 healthy adults (mean age 28.68±8.35). 25-Hydroxyvitamin D and LL-37 levels were determined in both saliva and serum samples by the Enzyme-linked immunosorbent assay (ELISA) using commercially available kits.
Results: 25-Hydroxyvitamin D levels in serum (median 5.92 ng/ml, min-max 2,7-10,4 ng/ml) correlated to LL-37 serum levels (62 ng/ml, min-max 18-378 ng/ml) (Pearson’s r 0.328, p=0.005), and 25-Hydroxyvitamin D levels in saliva (median 1,16ng/ml, min-max 0,54-2,12 ng/ml) strongly correlated to LL-37 salivary levels (median 44 ng/ml, min-max 6.5-205 ng/ml) (Pearson’s r 0.667, p<0.001).
Conclusions: Vit D salivary levels strongly correlate to LL-37 salivary levels. This finding enhances the significance of the vitamin D role in the immune response of the oral cavity.