Lactoferrin in Gingival Crevicular Fluid and Peripheral Blood during Experimental Gingivitis

Resistance and resilience to experimental gingivitis: a systematic scoping review

Background

This systematic scoping review aimed to identify changes in biomarkers of microbiological, immunological and biochemical origin during experimental gingivitis (EG) studies that might indicate resistance and resilience.

Methods

The term ‘experimental gingivitis’ was run in PubMed from inception to April 11th, 2018. From the 411 studies retrieved, 22 studies were included for this review.

Results

Studies reporting data on biomarker changes during and after full mouth EG trial were included. Two studies reported findings on changes in biomarkers of microbiological, 12 on immunological and eight on biochemical origin. Changes were reported in the induction phase, and occasionally in the resolution phase. The microbiological composition of both supragingival and subgingival dental plaque changed over the course of EG to a more pathogenic direction, but showed a shift back to a more normal composition. This indicates resilience of the oral microbiome. For immunological biomarkers, it was challenging to retrieve a robust pattern of changes across multiple studies. IL-1β and IL-6 in saliva and in gingival crevicular fluid increased during induction phase and returned in the resolution phase below baseline values. The biochemical parameters cystatin-SN, cystatin-S and lactoferrin in saliva were increased at the end of induction phase, however also here no clear pattern emerged based on all available studies.

Conclusions

More research is needed to investigate which microbiological, immunological, and biochemical biomarkers can be useful for future investigations into the resistance and resilience of the oral cavity to experimental gingivitis.

Electronic supplementary material

The online version of this article (10.1186/s12903-019-0889-z) contains supplementary material, which is available to authorized users.

Salivary Cytoprotective Proteins in Inflammation and Resolution during Experimental Gingivitis--A Pilot Study

Objective: The protective mechanisms that maintain periodontal homeostasis in gingivitis and prevent periodontal tissue destruction are poorly understood. The aim of this study was to identify changes in the salivary proteome during experimental gingivitis.

Study design: We used oral neutrophil quantification and whole saliva (WS) proteomics to assess changes that occur in the inflammatory and resolution phases of gingivitis in healthy individuals. Oral neutrophils and WS samples were collected and clinical parameters measured on days 0, 7, 14, 21, 28, and 35.

Results: Increased oral neutrophil recruitment and salivary cytoprotective proteins increased progressively during inflammation and decreased in resolution. Oral neutrophil numbers in gingival inflammation and resolution correlated moderately with salivary β-globin, thioredoxin, and albumin and strongly with collagen alpha-1 and G-protein coupled receptor 98.

Conclusions: Our results indicate that changes in salivary cytoprotective proteins in gingivitis are associated with a similar trend in oral neutrophil recruitment and clinical parameters.

Clinical relevance: We found moderate to strong correlations between oral neutrophil numbers and levels of several salivary cytoprotective proteins both in the development of the inflammation and in the resolution of gingivitis. Our proteomics approach identified and relatively quantified specific cytoprotective proteins in this pilot study of experimental gingivitis; however, future and more comprehensive studies are needed to clearly identify and validate those protein biomarkers when gingivitis is active.

Lactoferrin levels in gingival crevicular fluid and saliva of HIV-infected patients with chronic periodontitis

AIM

This study compared lactoferrin (LF) levels in the gingival crevicular fluid (GCF) and saliva between HIV-infected and noninfected patients with chronic periodontitis.

METHODS

For each subject, LF levels were analyzed in one shallow site (SS; PD ≤3 mm), one deep site (DS; PD >5 mm) and in resting whole saliva. Two groups, 28 HIV-infected and 10 noninfected, were selected.

RESULTS

Although the salivary LF levels were higher in HIV-infected than in noninfected individuals, especially in AIDS patients, this was not statistically significant (P > 0.05). Subgingival LF levels for SS and DS were lower among HIV-infected individuals, although AIDS patients showed the lowest levels. Age, smoking, gender, T CD4 lymphocytes levels and viral load did not influence subgingival LF levels, neither for SS nor for DP. Positive fungal culture was observed in 24 HIV-infected patients, but only observed in one in the control group. Overall, LF concentration was significantly higher in DS than SS, both in HIV-infected and noninfected individuals (P < 0.05) and salivary LF levels were always higher than GCF levels.

CONCLUSION

The data indicate that LF levels in the GCF and saliva are not different between HIV-infected and noninfected patients with chronic periodontitis.

Effect of periodontal therapy on lactoferrin levels in gingival crevicular fluid

BACKGROUND

The aim of this study was to evaluate lactoferrin quantification as a sensitive and objective method of detecting the degree of periodontal inflammation, oxidative stress and to monitor the effects of periodontal therapy.

METHODS

Fifty subjects were divided into two groups based on gingival index, probing pocket depth, clinical attachment loss and alveolar bone loss: healthy group and periodontitis group with generalized chronic periodontitis. Non-surgical periodontal therapy was rendered and crevicular fluid samples collected at baseline and four weeks after therapy for lactoferrin quantification using enzyme linked immunosorbent assay. The correlation between clinical parameters and lactoferrin levels was drawn and analysed for both groups.

RESULTS

The mean level of crevicular lactoferrin in the periodontitis group was 1857.21 ng/ml. The mean level decreased to 1415.03 ng/ml after treatment. The lowest lactoferrin concentration was seen in the healthy group (75.34 ng/ml). All clinical parameters correlated positively with lactoferrin levels.

CONCLUSIONS

The lactoferrin level was higher in the periodontitis group compared to the healthy group, and reduced with periodontal therapy. Higher levels were associated with higher values of clinical parameters, both before and after therapy. The data indicates that Lactoferrin plays an important role in periodontal disease and crevicular lactoferrin quantification can be a marker for detecting periodontal inflammation, oxidative stress and monitoring periodontal therapy.

Periodontitis, periodontopathic bacteria and lactoferrin

Lactoferrin (LF) is a component of saliva and is suspected to be a defense factor against oral pathogens including Streptococcus mutans and Candida albicans. Periodontitis is a very common oral disease caused by periodontopathic bacteria. Antimicrobial activities and other biological effects of LF against representative periodontopathic bacteria, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, and Prevotella intermedia, have been widely studied. Association of polymorphisms in LF with incidence of aggressive periodontitis and the role of LF in the gingival crevicular fluid as a marker of periodontitis severity have also been reported. Periodontopathic bacteria reside as a biofilm in supragingival and subgingival plaque. Our recent study indicated that LF exhibits antibacterial activity against planktonic forms of P. gingivalis and P. intermedia at higher concentrations, and furthermore, LF effectively inhibits biofilm formation and reduces the established biofilm of these bacteria at physiological concentrations. A small-scale clinical study indicated that oral administration of bovine LF reduces P. gingivalis and P. intermedia in the subgingival plaque of chronic periodontitis patients. LF seems to be a biofilm inhibitor of periodontopathic bacteria in vitro and in vivo.