Prevalence and virulence factors of Helicobacter pylori isolated from oral cavity of non-disease, gastritis, and gastric cancer patients.

Background/purpose: The oral cavity is considered a reservoir of Helicobacter pylori associated with gastric infection. It aimed to examine the prevalence of H. pylori strains from the oral cavity and gastric tissue of patients with different stage of gastric-diseases. Strains were further characterized for virulence genes, adhesion ability, and inflammation responses. Materials and methods: 11 non-disease, 15 gastritis, and 15 gastric cancer participated in the study. After clinical examination, gastric biopsies, saliva and plaque samples were collected and H. pylori levels were examined by real-time PCR and cultivation. The cagA and vacA genes were investigated from the culture strains. Adhesion ability and pro-inflammatory responses were analyzed in comparison between the presence of virulent genes and disease status. Results: Relatively poor periodontal condition was found among gastric cancer patients. Prevalence of H. pylori-positive was 84.8% and 19.5% by real-time PCR and cultivation, respectively. The cagA and vacA gene-positive strains were 52.6% and 5.3%, respectively, which were found more in gastric cancer patients. The cagA gene-positive strains were found to be higher in gastric cancer patients, and strains had significantly higher adhesion ability and pro-inflammation expressions than the cagA gene-negative strains. Conclusion: Colonization by H. pylori in oral cavity was confirmed, and the cagA gene-positive strains play a crucial role in both adhesion and inflammatory responses. The presence of H. pylori and its virulence gene in oral cavity should be received attention. An eradication of such strains from oral cavity may help to prevent the transmission and recolonization to gastric organs.

Unlocking the genetic potential of Lacticaseibacillus rhamnosus strains: Medical applications of a promising probiotic for human and animal health.

Lacticaseibacillus rhamnosus is a group of probiotic strains that have gained popularity for their potential health benefits such as promoting digestive health, boosting the immune system, improving lactose digestion, preventing and treating antibiotic-associated diarrhea, reducing the severity and duration of certain infections, and preventing the formation of dental plaque. In particular, L. rhamnosus strains SD4 and SD11 have promising human and animal health applications due to their ability to inhibit the growth of harmful pathogens. This study presents an in silico genomic analysis of L. rhamnosus strains SD4 and SD11. We analyzed draft genomes and conducted comparative genome analyses against several other probiotic strains, aiming to gain insights into the genomes of the two strains and to compare them to related strains isolated from other sources. We also aimed to clarify the functional mechanisms and adaptation of these strains to specific environments. Comprehensive insights into the genomes of L. rhamnosus SD4 and SD11 could enhance our understanding of their capacity to colonize, adapt, and exhibit probiotic properties after administration. This study holds significance in advancing our understanding of the potential health benefits associated with these strains and in elucidating the underlying mechanisms responsible for their effectiveness in humans and animals.

Prevalence and virulence factors of haemolytic Enterococcus faecalis isolated from root filled teeth associated with periradicular lesions: A laboratory investigation in Thailand.

AIM: Previous endodontic research has provided limited understanding of the prevalence and roles of haemolytic and non-haemolytic Enterococcus faecalis strains in root filled teeth. This study aimed to determine the prevalence of these strains in root filled teeth with periradicular lesions and investigate their associated virulence factors. METHODOLOGY: A total of 36 root canal samples were collected from 36 subjects. The prevalence of E. faecalis was determined using culture and PCR methods. Antibiotic susceptibility of haemolytic and non-haemolytic E. faecalis strains was assessed using the broth dilution assay. The cytokine stimulation in periodontal ligament (PDL) cells and neutrophil migration were evaluated using real-time PCR and migration assay, respectively. Cell invasion ability of the strains was assessed using a cell culture model. Additionally, the virulence gene expression of the haemolytic and non-haemolytic strains was investigated using real-time PCR. The Mann-Whitney U and Spearman's ρ tests were used to examine the significant difference between the two strains and to analyse the correlation between phenotype and gene expression, respectively. RESULTS: Enterococcus faecalis was detected in 33.3% and 88.9% of samples by culture and real-time PCR, respectively. Haemolytic strains were found in 36.4% of subjects. Non-haemolytic strains exhibited susceptibility to erythromycin and varying susceptibility to tetracycline, while all haemolytic strains were resistant to both antibiotics. Haemolytic strains significantly upregulated the expression of IL-8, OPG and RANKL in PDL cells (p < .05). Notably, the fold increases in these genes were higher: IL-8 (556.1 ± 82.9 vs. 249.6 ± 81.8), OPG (2.2 ± 0.5 vs. 1.3 ± 0.2) and RANKL (1.8 ± 0.3 vs. 1.2 ± 0.1). Furthermore, haemolytic strains had a greater effect on neutrophil migration (68.7 ± 15.2% vs. 46.9 ± 11.4%) and demonstrated a higher level of internalization into oral keratinocyte cells (68.6 ± 0.4% vs. 33.8 ± 0.5%) (p < .05). They also showed enhanced expression of virulence genes associated with haemolysin, surface proteins, collagen-binding and aggregation substances. Gelatinase activity was only detectable in non-haemolytic strains. CONCLUSIONS: This study revealed that haemolytic strains E. faecalis possessed enhanced abilities in host invasion and a higher abundance of virulence factors, suggesting their potential contribution to more severe disease manifestations.

Periodontal diseases in Thai schoolchildren. Clinical and microbiological observations.

The prevalence of periodontitis among Thai schoolchildren is unknown. In a cross-sectional study, the prevalence and severity of periodontal diseases, in a group of Thai schoolchildren, along with the presence and numbers of bacterial species commonly associated with periodontitis were investigated. A consent form was sent out to 192 schoolchildren in one school (Chanachanupathom School) in Chana, Southern Thailand (in the age range of 12-18 years) and 119 attended for a clinical and microbiological examination. Clinical recordings included number of teeth present, DMFT, plaque index, bleeding index, clinical attachment loss (CAL), and probing pocket depth (PPD). Pooled plaque samples were analyzed with culture and qPCR against bacteria associated with periodontitis. The children had low caries experience (DMFT = 3.2 ± 2.3), poor oral hygiene, high bleeding scores, and 67 (56.3%) had at least one interproximal site with CAL ≥ 1 mm. Thirty-seven (31.1%) of the children were diagnosed with periodontitis stage I, and sixteen (13.4%) were classified as periodontitis Stage II. Aggregatibacter actinomycetemcomitans was sparsely found in all but the healthy clinical groups (gingivitis, periodontitis Stage I and II), while the groups showed a high prevalence of Fusobacterium spp., Prevotella intermedia/nigrescens, and Campylobacter species as well as of the periodontitis-associated species Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia. Thai schoolchildren have poor oral hygiene with abundant amounts of plaque and high presence of bleeding. Early onset periodontitis is common but mostly in its mild form and is not associated with the presence of A. actinomycetemcomitans.

Short-term use of Lacticaseibacillus rhamnosus SD11 and the oral microbiome: Low caries RCT study.

OBJECTIVES: The objective of the study was to investigate the effect of short-term lozenges containing Lacticaseibacillus rhamnosus SD11 on cariogenic pathogens and on oral microbiota. MATERIALS AND METHODS: This double-blind, randomized, controlled trial included 121 subjects and was randomly divided into the control and probiotic group. All subjects were blindly administered to receive the control- or probiotic L. rhamnosus SD11 lozenges every day for 4 weeks and then followed up for another 4 weeks. RESULTS: After probiotic consumption, the probiotic group had significantly lower levels of Streptococcus mutans and significantly higher levels of total lactobacilli at 4 and 8 weeks compared with the baseline. The 16S rRNA sequencing revealed an increase in bacterial diversity and beneficial bacteria in the Firmicutes phylum, Bacilli class, and a reduction in the mutans streptococci group in the probiotic group. The opposite results were found in the control group. This study did not find any caries increment, nor did the subjects have any side effects after product consumption. CONCLUSION: With the limitation of a short-time study in low caries children, it showed that L. rhamnosus SD11 could increase beneficial bacteria in the Firmicutes phylum and Bacilli class that might support good oral health in children.

Characterization of adhesion, anti-adhesion, co-aggregation, and hydrophobicity of Helicobacter pylori and probiotic strains.

Objectives: To characterize the adhesion ability of nine Helicobacter pylori strains and eight probiotics in human oral keratinocyte cells (H357 cells) in comparison to intestinal cells (Caco-2 and HIEC-6 cells). Subsequently, the anti-adhesion and co-aggregation abilities of the selected probiotic strains on H. pylori strains were investigated. Methods: Nine H. pylori strains, including H. pylori ATCC43504 (type strain), and 8 clinical strains, were isolated from oral samples of three patients (one non-disease, one gastritis patient, and one gastric cancer patient). Eight selected probiotic strains were used, as follows: Lacticaseibacillus paracasei SD1, Lacticaseibacillus rhamnosus SD4, L. rhamnosus SD11, Limosilactobacillus fermentum SD7, L. rhamnosus GG, Limosilactobacillus reuteri ATCC-PTA6475, Lacticaseibacillus casei Shirota, and L. paracasei CNCM I-1572. The adhesion and anti-adhesion abilities of H. pylori and the probiotic strains were investigated in H357, Caco-2, and HIEC-6 cells. Co-aggregation at various pHs, hydrophobicity, and surface receptors of the cell lines for H. pylori strains were examined. Results: All probiotic and H. pylori strains adhered to H357 significantly better than Caco-2, and HIEC-6 cells. Three probiotic strains (SD7, SD4, SD11) showed significantly higher adhesion than others. Of the clinical H. pylori strains, isolates from a gastric cancer patient had the highest adhesion ability to all of the cell lines tested. Probiotic strains that exhibited high adhesion ability provided high anti-adhesion and co-aggregation against H. pylori strains. Acidic conditions encouraged the co-aggregation of probiotics to H. pylori strains. Conclusion: This study provides information relating to the adhesion abilities of clinical H. pylori and probiotic strains to the oral mucosa when compared to the intestinal mucosa. Certain probiotic strains may be useful for the successful eradication of H. pylori infection via anti-adhesion and co-aggregation.

Evaluation of Potential Probiotic Properties of Lactobacillus and Bacillus Strains Derived from Various Sources for Their Potential Use in Swine Feeding.

Beneficial effects of probiotics are relevant to the various potential properties of individual strains, and they may also relate to the original sources of the probiotic strains. This study aimed to characterize the potential probiotic properties of the strains originating from various sources for probiotics use in swine feeding. A total of 9 potential probiotic strains, seven lactobacilli and 2 bacilli, were examined for antimicrobial production against swine pathogens, adhesion and anti-adhesion of potential probiotic strains to IPEC-J2 cells, aggregation ability, host defense peptide expression, and hemolytic assay. The results highlight that all strains derived from different sources could exhibit probiotic properties, although different abilities were observed. L. rhamnosus SD11 exhibited the highest inhibitory effect against all pathogens compared to other strains. Bacillus licheniformis KMP-9, B. subtilis KMP-N004, and L. fermentum SD7 gave the highest internalization and that related to high abilities of exclusion, competition, and displacement inhibition to pathogens. Such strains also gave a higher co-aggregation to all pathogens compared to other potential probiotic strains. L. rhamnosus GG, L. fermentum SD7, L. rhamnosus SD4, and B. subtilis KMP-N004 had significantly higher pBD-2 mRNA expression than other strains. None of potential probiotic strains showed hemolytic activity. In conclusion, the strains derived from either humans or animals possessed desirable probiotic properties including inhibition against porcine pathogens, adhesion capacity to porcine enterocytes, anti-adhesion pathogens to porcine enterocytes, and modulated innate immunity. Results indicate that these probiotic strains may be good candidates for use in swine feeding to reduce the risk of infection.

Anti-cancer Properties of Potential Probiotics and Their Cell-free Supernatants for the Prevention of Colorectal Cancer: an In Vitro Study.

This study aimed to characterize the anti-cancer properties of potential probiotics (Lacticaseibacillus paracasei SD1, Lacticaseibacillus rhamnosus SD4, Lacticaseibacillus rhamnosus SD11, and Lacticaseibacillus rhamnosus GG) and their cell-free supernatants (CFS) for the prevention of colorectal cancer (CRC), which including anti-bacterial and anti-inflammation activities against pathogens associated with CRC (Fusobacterium nucleatum, Porphyromonas gingivalis, ETEC, and Salmonella enterica). The expression of human ß-defensin (2-4) and IL-10 after being stimulated with probiotics was also examined. In addition, anti-cancer activity of CFS and probiotic growth under intestinal conditions were determined. An in vitro study was conducted in the Caco-2 and HIEC-6 cells. Results showed that probiotic cells and their CFS displayed different antibacterial activity, and L. rhamnosus SD11 showed the strongest inhibition of the growth of pathogens. Additionally, both probiotic cell walls and their CFS suppressed pro-inflammatory cytokines after being stimulated with pathogens in Caco-2 and HIEC-6 cells. L. paracasei SD1 and L. rhamnosus SD11 showed significantly higher suppression levels than others and also both strains can stimulate highly expression of hBD (2-4) and IL-10. The CFS of L. paracasei SD1 and L. rhamnosus SD11 inhibited significantly high growth of Caco-2 cells but not much in HIEC-6 cells. Furthermore, all probiotics adhered to Caco-2 and HIEC-6 cells, and L. rhamnosus SD4 showed the highest adhesion to both cells. They could survive more than 70% in intestinal conditions. In conclusion, results indicate that potential probiotics tested exhibited various anti-cancer properties, which may be good candidates used as biotherapy for the prevention or to delay the progression of CRC.

Characterization of Short Chain Fatty Acids Produced by Selected Potential Probiotic Lactobacillus Strains.

Short-chain fatty acids (SCFAs), particularly butyrate, have received considerable attention with regard to their anti-cancer efficacy in delaying or preventing colorectal cancer. Several studies have reported that certain probiotic strains could produce SCFAs; however, different strains yielded different amounts of SCFAs. This study explored the ability to produce SCFAs of the following probiotic strains: Lacticaseibacillus paracasei SD1, Lacticaseibacillus rhamnosus SD4, Lacticaseibacillus rhamnosus SD11, and Lacticaseibacillus rhamnosus GG. L. paracasei SD1 and L. rhamnosus SD11 exhibited high butyrate production, particularly when the strains were combined. The functions of the SCFAs were further characterized; the SCFAs exerted a positive anti-cancer effect in the colon via various actions, including inhibiting the growth of the pathogens related to colon cancer, such as Fusobacterium nucleatum and Porphyromonas gingivalis; suppressing the growth of cancer cells; and stimulating the production of the anti-inflammatory cytokine IL-10 and antimicrobial peptides, especially human ß-defensin-2. In addition, the SCFAs suppressed pathogen-stimulated pro-inflammatory cytokines, especially IL-8. The results of this study indicated that selected probiotic strains, particularly L. paracasei SD1 in combination with L. rhamnosus SD11, may serve as good natural sources of bio-butyrate, which may be used as biotherapy for preventing or delaying the progression of colon cancer.

Efficacy of Moraceae with chlorhexidine mouthwash on the microbial flora of critically ill intubated patients: a randomized controlled pilot study.

Critically ill intubated patients are routinely provided with chlorhexidine (CHX) for their mouth washing, but CHX mouthwash induces several complications. In this study, we aimed to evaluate the efficacy and safety of Moraceae with CHX mouthwash in the reduction of oral bacterial count in critically ill patients and to compare it with CHX-alone mouthwash. This double-blind, randomized, controlled trial included critically ill patients receiving mechanical ventilation. The patients were randomly divided into two groups based on the Modified Beck oral assessment score. The primary endpoint was a reduction in oral bacterial counts after mouth washing on day 1 and day 4. Thirty patients were included in this study; 15 patients received Moraceae with CHX mouthwash and 15 patients received CHX-alone mouthwash. The oral bacterial counts in the Moraceae with CHX group did not differ from the CHX group after mouth washing on day 1 and day 4 of admission. The patients in the CHX group experienced more intolerable taste than those in the Moraceae group (60% vs. 13.3%, P = 0.008). Moraceae with CHX mouthwash had the same effectiveness as CHX alone on bacterial flora but exhibited less intolerable side effects than CHX alone.Trial registration: TCTR20190530003; 30/05/2019.

Effects of potential probiotics on the expression of cytokines and human ß-defensins in human gingival epithelial cells and in vivo efficacy in a dog model.

OBJECTIVES: The aims of this study were to examine the effects of probiotic strains on the expression of cytokines and human ß-defensins-2-4 in human gingival epithelial cells and to investigate the in vivo efficacy of probiotics in a dog model. DESIGN: Selected probiotics, Lacticaseibacillus paracasei SD1, L. rhamnosus SD4, L. rhamnosus SD11 and Limosilactobacillus fermentum SD7, were examined for the expression of human ß-defensins-2-4, and cytokine responses after stimulated by various periodontopathogens. Subsequently, an in vivo study was set as a randomized, double-blind, placebo-controlled intervention in a dog model. A total of 20 dogs with mild gingivitis were randomly assigned to either the probiotic or control group. The effects of probiotics on periodontopathogenic- and cytokine levels were analyzed after 4 weeks of intervention. RESULTS: It showed that all probiotics could induce human ß-defensins-2-4, interleukin-1ß, interleukin-6, interleukin-8, and tumor necrosis factor-α expressions in human gingival epithelial cells; however, a significant difference had been found among the strains. When individual probiotic strain was combined to periodontopathogens, a significant reduction of IL-8 expression was found. Results of the in vivo study demonstrated that the bacterial levels, especially Porphyromonas gingivalis, and the interleukin-8 levels were significantly decreased after receiving the probiotic products compared to the controls. CONCLUSION: The results of the in vitro and in vivo studies in dogs are encouraging to support the effectiveness of a mixture of probiotic treatments for improvement of periodontal health by reducing periodontopathogens and interleukin-8 levels. Therefore, such probiotics preparation could possibly have therapeutic potential in human periodontitis.

Significant elevation of salivary human neutrophil peptides 1-3 levels by probiotic milk in preschool children with severe early childhood caries: a randomized controlled trial.

OBJECTIVES: To determine salivary human neutrophil peptides 1-3 (HNP1-3) levels in caries-free preschool children and in those with early childhood caries (ECC) or severe-ECC, in a daily probiotic group, receiving reconstituted milk with the probiotic Lactobacillus paracasei SD1 once daily; a triweekly probiotic group, receiving the probiotic milk 3 days a week; and a placebo group. MATERIALS AND METHODS: Oral examination and unstimulated whole saliva collection were conducted in 354 children at baseline, 6 months after intervention (T6), and after probiotic discontinuation (T12). Of the 354, adequate volume of saliva samples from 268 children were simultaneously analyzed for Streptococcus mutans and total lactobacilli levels using qPCR and for HNP1-3 levels using ELISA. RESULTS: In the severe-ECC status, significant increases in the median HNP1-3 levels at T12 were found in both daily and triweekly probiotic groups (p < 0.001). The median S. mutans levels in the daily group were significantly decreased at T6 and T12 (p < 0.01), whereas the median total lactobacilli levels were significantly increased at T6 (p < 0.001). Significantly inverse correlations between altered HNP1-3 and S. mutans levels and significant decreases in caries progression were found in both probiotic groups (p < 0.05). CONCLUSIONS: In the severe-ECC status, daily or triweekly consumption of L. paracasei SD1 significantly enhanced salivary HNP1-3 levels, but reduced S. mutans levels, possibly resulting in reduction of caries progression. CLINICAL RELEVANCE: Significant enhancement of salivary HNP1-3 levels by probiotic consumption is associated with reduction in S. mutans levels, consistent with diminished caries progression in children with severe-ECC.

Efficacy of Probiotic Milk for Caries Regression in Preschool Children: A Multicenter Randomized Controlled Trial.

This multicenter double-blind randomized controlled trial aimed to determine the efficacy of daily or triweekly consumption of reconstituted milk powder, containing Lactobacillus paracaseiSD1, in preschool children for caries prevention. A 6-month intervention was conducted in 487 children (aged 37.6 ± 9.2 months) with ≤4 decayed teeth from 8 childcare centers. Using stratified block randomization, participants were randomly allocated into 3 groups, comprising: (1) daily probiotic, receiving probiotic milk once daily, (2) triweekly probiotic, randomly receiving probiotic milk 3 days a week and the placebo milk for the remaining 4 days, and (3) placebo, receiving milk without probiotics. Each tooth surface was assessed for caries status using the modified Nyvad criteria at baseline (T0), 6 (T6) and 12 (T12) months after T0. Study outcomes were caries transition, including caries progression and regression during the T0-T6, T6-T12 and T0-T12 periods. Negative binomial regression with a generalized linear model was used to estimate the caries outcomes, which were reported as incidence rate ratios (IRRs) and 95% confidence intervals (CIs). At baseline, caries prevalence and mean decayed surfaces were 81.9% and 7.29 ± 7.60, respectively. Three groups were balanced at baseline with an overall dropout rate of 25.2%. After adjusting for age, sex, and the number of noncavitated and cavitated caries at baseline, a decreased caries risk during T0-T6 was shown in both the daily and triweekly probiotic groups (adjusted IRR 0.83, 95% CI 0.72-0.96 in both groups) and during T0-T12 (adjusted IRR 0.84, 95% CI 0.76-0.94, and adjusted IRR 0.86, 95% CI 0.76-0.96, respectively) compared to the placebo group. In contrast, significantly increased regressive surfaces were demonstrated during T0-T6 by adjusted IRR 1.76 (95% CI 1.25-2.48) and 2.01 (95% CI 1.42-2.85) and during T0-T12 by adjusted IRR 1.98 (95% CI 1.50-2.61) and 1.92 (95% CI 1.45-2.55) for the daily and triweekly groups, respectively. In conclusion, probiotic milk consumption either daily or triweekly can modestly prevent new caries, but considerably reverse carious lesions, suggesting that a daily or triweekly dose interval is sufficient to reverse carious lesions.

Oral Lactobacillus strains reduce cytotoxicity and cytokine release from peripheral blood mononuclear cells exposed to Aggregatibacter actinomycetemcomitans subtypes in vitro.

BACKGROUND: This study evaluated the effect of oral lactobacilli on the cytotoxicity and cytokine release from peripheral blood mononuclear cells (PBMCs) when exposed to Aggregatibacter actinomycetemcomitans subtypes in vitro. The supernatants and cell wall extracts (CWEs) of eight A. actinomycetemcomitans strains, representing different subtypes, and three Lactobacillus strains were used. The PBMCs from six blood donors were exposed to supernatants and CWEs of A. actinomycetemcomitans or Lactobacillus strains alone or combinations and untreated cells as control. The cytotoxicity was determined by trypan blue exclusion method and IL-1ß secretion by ELISA. TNF-α, IL-6, and IL-8 secretions were measured using Bioplex Multiplex Immunoassay. RESULTS: Supernatants or CWEs from all bacterial strains showed cytotoxicity and IL-1ß secretion and the subtypes of A. actinomycetemcomitans showed generally a significantly higher effect on PBMCs than that of the Lactobacillus strains. Two highly toxic A. actinomycetemcomitans strains (JP2 and JP2-like) induced a higher response than all other strains. When combined, Lactobacillus significantly reduced the toxicity and the IL-1ß secretion induced by A. acinomycetemcomitans. The effect varied between the subtypes and the reduction was highest for the JP2 and JP2-like strains. The Lactobacillus paracasei strain SD1 had a higher reducing effect than the other Lactobacillus strains. This strain had a consistent reducing effect on all subtypes of A. actinomycetemcomitans cytotoxicity, and release of IL-1ß, IL-6, IL-8, and TNF-α from PBMCs of the blood donors. A strong and significant variation in cytokine release between the six blood donors was noticed. CONCLUSIONS: Lactobacillus spp. and L. paracasei SD1 in particular, showed a limited but statistically significant reducing interaction with A. actinomycetemcomitans toxicity and release of cytokines in vitro.

Fermented milk containing a potential probiotic Lactobacillus rhamnosus SD11 with maltitol reduces Streptococcus mutans: A double-blind, randomized, controlled study.

BACKGROUND/PURPOSE: Sucrose has been considered as a cariogenic substrate due to large amounts of acid production after fermentation by certain oral bacteria, thus sugar alcohols are often used to replace sucrose. The aims of this study were to investigate the effect of maltitol on the growth and acid production of Streptococcus mutans and Lactobacillus rhamnosus-SD11 compared to various sugars, and to examine whether the fermented milk containing a potential probiotic L. rhamnosus-SD11 with maltitol could reduce S. mutans. MATERIALS AND METHODS: The acid production of tested sugars by cariogenic S. mutans was measured using pH meter. In a clinical trial, 123 children were recruited and randomly assigned to either the probiotic- or control-fermented milk, once daily for 4 weeks. The target bacteria levels in the saliva were examined using a real-time PCR at baseline, 4 and 8 weeks. The oral examination was recorded at the baseline and 8 weeks. RESULTS: The results showed that maltitol exhibited less acid production than simple sugars. In the clinical trial, a significant reduction of salivary total streptococci and S. mutans occurred, while the levels of salivary lactobacilli significantly increased in the probiotic group compared to the control group after receiving the probiotic fermented milk. CONCLUSION: The daily consumption of the fermented milk containing L. rhamnosus-SD11 with maltitol had beneficial effects on oral health by reducing salivary S. mutans. Thus, the substitution of simple sugars by maltitol in dairy products containing L. rhamnosus-SD11 may be an alternative way to prevent the risk of caries.

Reduction of Streptococcus mutans by probiotic milk: a multicenter randomized controlled trial.

OBJECTIVE: To investigate the effects of probiotics, Lactobacillus paracasei SD1, on the quantities of Streptococcus mutans in saliva and plaque samples of preschool children. DESIGN: This randomized trial recruited 487 preschool children from eight childcare centers. Participants were assigned to receive a 6-month course of placebo milk daily (group I), probiotic milk either daily (group II) or three days a week (triweekly, group III). The absolute quantities of S. mutans and total lactobacilli in the saliva and plaque samples at baseline (T0), after intervention (T6), and 6 months after discontinuation (T12) were assessed by qPCR. RESULTS: Of 487 children, 354 completed all follow-up periods. However, only 268 children (3.2 ± 0.8 years old; groups I = 86, II = 89, and III = 93) provided adequate saliva for qPCR. Whereas the quantities of S. mutans were significantly decreased in groups II and III compared to group I in the saliva and plaque samples at T6 and T12, those of total lactobacilli were significantly increased (p < 0.0167). There was no difference in the quantities of S. mutans or total lactobacilli between groups II and III at any period. Significant changes in the quantities of S. mutans and total lactobacilli lasted until T12 compared to T0 (p < 0.0167). CONCLUSIONS: Probiotic administration daily or triweekly reduces S. mutans quantities, whereas it increases total lactobacilli quantities that persists at least 6 months after discontinuation in the saliva and plaque samples of preschool children. CLINICAL RELEVANCE: Daily or triweekly consumption of L. paracasei SD1 supplemented in milk may help prevent dental caries in preschool children.

Increasing salivary IgA and reducing Streptococcus mutans by probiotic Lactobacillus paracasei SD1: A double-blind, randomized, controlled study.

BACKGROUND/PURPOSE: Our previous study revealed that probiotic Lactobacillus paracasei SD1 could reduce mutans streptococci as evaluated by cultivation-method as well as stimulate innate immunity. This study aimed to further investigate the effect of the probiotic on various oral bacteria by real-time PCR and salivary IgA levels. MATERIALS AND METHODS: Forty children were included by randomization from either probiotic or control group in the previous study. The probiotic or control received milk-powder with or without L. paracasei SD1, respectively once daily for 6 months. Saliva were collected at baseline 3-, 6-, and 12-months and were evaluated for total bacteria, total lactobacilli (TL), L. paracasei/L. casei (LP/LC), total streptococci (TS) and Streptococcus mutans using the real-time PCR. The salivary IgA (sIgA) was examined using the ELISA method. RESULTS: All target bacterial levels were not significantly different at baseline in both groups. After milk-powder consumption, TL and LP/LC levels were significantly increased in the probiotic group, whereas TS and S. mutans levels were significantly decreased compared to baseline. TS and S. mutans levels were significantly lower, while the sIgA was greater in the probiotic compared to the control group. In the probiotic group, a positive correlation was found between LP/LC and sIgA, while negative correlations were observed between TS or S. mutans levels and sIgA. CONCLUSION: L. paracasei SD1 could control S. mutans level and could stimulate sIgA. Results indicate that the L. paracasei SD1 strain may have a benefit for prevention of dental caries.

Reducing mutans streptococci and caries development by Lactobacillus paracasei SD1 in preschool children: a randomized placebo-controlled trial.

OBJECTIVE: To examine a reducing effect of Lactobacillus paracasei SD1 on MS and caries in preschool children. MATERIALS AND METHODS: A total of 124 children, aged 1.5-5 years old, participated and were randomly assigned to the probiotic or control group. The probiotic group received L. paracasei SD1-milk and the control group received standard-milk once daily for 3 months. MS/lactobacilli were enumerated and the caries score was examined. Association between probiotic consumption and bacterial level, or caries progression was assessed by a multivariate logistic regression. This study was registered at the Thai-Clinical-Trials-Registry (TCTR20140903001). RESULTS: Probiotic was found to be a factor associated with the MS level. Children in the probiotic group had a significantly lower risk of an increase in the MS level than in the control group after receiving the probiotic milk at 3- and 4-months with p < .001 and p = .040, respectively. Probiotic significantly reduced the risk for caries compared to the control group (p = .016). There were no adverse effects or non-compliance reported in either group. CONCLUSIONS: Consumption of milk powder containing L. paracasei SD1 resulted in a reduction of both salivary MS and delayed new caries development, and the strain is safe for use in young children. Results suggest that L. paracasei SD1 may be an alternative way for caries prevention in young children.

Pro-inflammatory cytokine responses in human gingival epithelial cells after stimulation with cell wall extract of Aggregatibacter actinomycetemcomitans subtypes.

Varying cytokine responses of human gingival epithelial cells (HGECs) by Aggregatibacter actinomycetemcomitans subtypes have been found. Most studies have used reference strains, whereas a few has evaluated the cytokine expression in response to clinical subtypes of this bacterial species. This study aimed to examine whether there was any difference in cytokine responses of HGECs stimulated with cell wall extract (CWE) from A. actinomycetemcomitans subtypes included clinical strains from Thai adult periodontitis, various serotypes and non-serotypeable strains, strains from deep or shallow pockets, and reference serotype strains. Totally 50 clinical strains and 7 reference strains of A. actinomycetemcomitans were analyzed for the expression of IL-1ß, IL-6, IL-8, and TNF-α mRNAs in HGECs by real time-PCR, and the IL-8 concentrations in cell-free supernatant measured using ELISA. An in vitro effect of released IL-8 on neutrophil migration was examined using transwell chambers. Result showed that among four cytokines studied, IL-8 mRNA was highly up-regulated by both clinical and reference strains. Serotype f revealed the highest expression compared to other serotypes. The JP2-like leukotoxin promoter gene and non-serotypeable (NS1 and NS2) demonstrated lower IL-8 responses compared to serotypeable strains, and IL-8 responses upon stimulation with clinical strains from deep pockets were also significantly lower than those isolated from shallow pockets (P < 0.01). Our findings suggest that the clinical isolates of A. actinomycetemcomitans associating with deep pockets, JP2-like leukotoxin promoter gene, NS1, and NS2 may interfere neutrophil function via minimal and immunosuppressing IL-8 responses, which may enhance their survival and virulence.

Screening for antibacterial and antibiofilm activity in Thai medicinal plant extracts against oral microorganisms.

To evaluate the antibacterial activity of 12 ethanol extracts of Thai traditional herb against oral pathogens. The antibacterial activities were assessed by agar well diffusion, broth microdilution, and time-kill methods. Antibiofilm activity was investigated using a 3-[4,5-dimethyl-2-thiazolyl]-2,5-diphenyl-2H-tetrazolium-bromide (MTT) assay. High performance liquid chromatography (HPLC), thin layer chromatography (TLC) fingerprinting, and TLC-bioautography were used to determine the active antibacterial compounds. Piper betle showed the best antibacterial activities against all tested strains in the minimal inhibitory concentration and minimal bactericidal concentration, ranged from 1.04-5.21 mg/mL and 2.08-8.33 mg/mL, respectively. Killing ability depended on time and concentrations of the extract. P. betle extract acts as a potent antibiofilm agent with dual actions, preventing and eradicating the biofilm. The major constituent of P. betle extract was 4-chromanol, which responded for antibacteria and antibiofilm against oral pathogens. It suggests that the ethanol P. betle leaves extract may be used for preventing oral diseases.