RESUMEN
Introduction: In the current study, we evaluated the effectiveness of two well-defined probiotic strains, Lactobacillus paracasei LPc-G110 (CCTCC M 2013691) and Lactobacillus plantarum GOS42 (DSM 32131), during an experimental gingivitis challenge. The primary objective was to evaluate clinically the effectiveness of lozenges containing one of the two oral probiotic strains, compared with placebo lozenges, on the gingival bleeding (bleeding on marginal probing; BOMP change) after a two-week experimental gingivitis period. The secondary objectives were to assess the effects of the test products on gingival health (Modified Gingival Index; MGI), dental plaque accumulation and fluorescence, and the dynamics of immunological and microbiological aspects after the wash-in phase, followed by a two-week period refraining from oral hygiene and a two-week wash-out phase. Methods: This single-center challenge intervention study was a triple-blind randomized placebo-controlled clinical trial with three parallel groups. The full study population consisted of 117 healthy 18-55 years old human volunteers. Subjects were instructed to use one lozenge, 3 times daily after each meal, containing either L. plantarum, L. paracasei, or lozenges without probiotics (placebo group). After a 2-week wash-in period, the subjects were requested to refrain from any form of oral hygiene for 2 weeks. Results: There were no differences in the primary outcome (BOMP change) among the groups. However, gingival health (MGI) in individuals from the groups exposed to the test products recovered better from experimental gingivitis than the individuals in the placebo group (p = 0.021, one-way ANOVA). The two test products inhibited pro-inflammatory cytokine IL-1ß production, measured in saliva, during the experimental gingivitis period. Both test strains significantly reduced bacterial DNA in tongue samples and L. paracasei strain showed stronger microbiome-modulating potential than the L. plantarum strain. Conclusions: The two tested lozenges with the L. paracasei or L. plantarum strains did show potential for beneficial effects for the oral health of the host during experimental gingivitis to the oral ecosystem.
RESUMEN
Background: Probiotic bacteria with anti-inflammatory properties have the potential to be of therapeutic benefit in gingivitis. Objective: To evaluate the effects of potential probiotic strains on inflammatory mediators involved in early gingivitis using an ex vivo inflammation model. Methods: Strains were screened in viable and attenuated forms for effects on bacterial lipopolysaccharide (LPS)-stimulated release of interleukins (IL)-1ß, -6 and -8, tumor necrosis factor-α, prostaglandin E2 and 8-isoprostane from human primary monocytes, and then, if anti-inflammatory effects were shown, on IL-1ß-stimulated release of inflammatory mediators from primary gingival fibroblasts. Lead strains were evaluated for optimal dosing, batch-to-batch variation and functional consistency in toothpaste. Results: Twenty-one of 73 strains showed anti-inflammatory effects in monocytes; of which, seven showed effects in both viable and attenuated forms. Seven of 14 strains showed effects in fibroblasts. Strains Lactobacillus paracasei LPc-G110(SYBIO-15) and Lactobacillus plantarum GOS42(SYBIO-41) induced statistically significant dose-dependent reductions in the release of multiple inflammatory mediators from monocytes, which were consistent across batches. Viable L. paracasei LPc-G110 tooth paste significantly reduced IL-6, IL-8 and prostaglandin E2 release from monocytes versus placebo. Conclusion: Strains L. paracasei LPc-G110 and L. plantarum GOS42 have potential for use as probiotics in oral care products to reduce gingival inflammation.
RESUMEN
Psychosocial stress has been shown to induce inflammatory reactions, followed by the release of immunosuppressive glucocorticoids. This may be mediated by catecholamines or other stress reactive substances such as neuropeptides or cytokines. We here set out to explore the effects of acute psychosocial stress on plasma levels of substance P (SP), a possible mediator of stress-induced inflammatory reactions, and interleukin-1 receptor antagonist (IL-1ra). Twelve healthy male subjects (mean age 27 yrs.) were subjected to the psychosocial stress test "Trier Social Stress Test" (TSST) and a resting control condition. Blood and saliva samples were taken before, as well as 1, 20, 45, and 90 min after TSST or rest, respectively. Salivary cortisol and plasma SP and IL-1ra were measured using immunoassays, salivary alpha-amylase (sAA) was measured by an enzyme kinetic method, and plasma epinephrine (E) and norepinephrine (NE) were measured by HPLC. The TSST induced immediate increases of E, NE, and sAA, and a delayed increase of free cortisol. Plasma IL-1ra showed an even further delayed peak at 90 min after stress. Plasma levels of SP did not respond to stress. No significant associations between changes of stress hormones and IL-1ra or SP were found. We conclude that substance P, epinephrine, and norepinephrine are probably not involved in mediating peripheral inflammation following psychosocial stress, at least with respect to IL-1ra. Further studies have to reveal the mechanisms involved in the stress-induced up regulation of IL-1ra.