Salivary lactoferrin and low‐M_r mucin MG2 in Actinobacillus actinomycetemcomitans‐associated periodontitis

Abstract

Concentrations and output of lactoferrin and of low-Mr mucin MG2 were determined in saliva of subjects suffering from Actinobacillus actinomycetemcomitans-associated periodontal disease and healthy subjects. Periodontal patients were clinically examined and a microbiological sample was taken from the deepest bleeding pockets in each quadrant. The number of viable A. actinomycetemcomitans was determined in the sampled sites of each patient. The MG2 output in the diseased subjects (13.6 microg protein/min) was decreased at least by a factor three compared to periodontal healthy subjects (44.3 microg protein/min). On the other hand, output of lactoferrin was not significantly different in healthy (9.5 microg/min) and diseased subjects (7.6 microg/min). Western analyses demonstrated a higher iron-saturation of lactoferrin in diseased subjects in comparison with the healthy subjects. Lactoferrin degrading enzymes, probably derived from microbial sources, could be detected in saliva of the periodontally diseased subjects, but not in saliva of healthy subjects. The combination of iron-saturation and degradation of lactoferrin suggests that anti-microbial properties of lactoferrin are diminished in periodontitis patients. Moreover, the low concentration of mucin MG2 suggests a decline in mucin defence and consequently a higher susceptibility for oral infection. A negative correlation (r= -0.4, p < 0.05) between the number of subgingival A. actinomycetemcomitans and lactoferrin in saliva suggested that low concentrations of lactoferrin favour the growth of the bacterium. These data indicate that a decline in the salivary defence system might increase the risk for oral infection by A. actinomycetemcomitans.

Estimation of Levels of Salivary Mucin, Amylase and Total Protein in Gingivitis and Chronic Periodontitis Patients

“…Our study is in accordance with the study done by Groenink et al, [33] who showed that MG2 output was decreased in individuals with aggressive periodontitis in comparison with periodontal healthy subjects.…”

Saliva: A Cutting Edge in Diagnostic Procedures

“…Lactoferrin is upregulated in the salivary secretions in gingival inflammation and periodontal diseases as compared to normal healthy individuals. It also bears a correlation with the A. actinomycetemcomitans species [16]. Histatin is another salivary protein with antimicrobial properties which neutralizes the endotoxic lipopolysaccharides located on Gramnegative bacteria.…”

Thematic Review Series: Skin Lipids. Antimicrobial lipids at the skin surface

“…(4,(10)(11)(12) and antimicrobial proteins and peptides. These include lysozyme (13,14), lactoferrin (15,16), acidic proline-rich proteins (17,18), plunc (19,20), salivary mucin glycoprotein (16,21), histatin (13,17,22), defensin HBD1 (23,24), defensin HBD2 (25)(26)(27), defensin HBD3 (26,27), defensin HBD4 (26,27), and hCAP18/LL-37 (28). Fatty acids and long-chain bases found at the skin surface have strong bactericidal activity (29)(30)(31)(32)(33).…”