Triclosan antimicrobial activity against dental-caries-related bacteria

Triclosan (TCS) is a chlorinated diphenyl ether and a possible active agent against microorganisms. Due to its probability of reducing dental plaque accumulation, TCS can be added as a substance for oral hygiene. Aim: To evaluate the efficacy and antimicrobial capacity of TCS against Pseudomonas aeruginosa and Streptococcus mutans. Methods: This work evaluates the percentage of bacteria inhibition of P. aeruginosa (ATCC 27853) and S. mutans (ATCC 25175). TCS concentrations between 2 and 128 µg.mL-1 were tested. Results: An inhibitory potential of TCS was found against S. mutans. No percentage of inhibition was detected against P. aeruginosa (technical and biological triplicate). Conclusion: TCS, an antimicrobial agent used in dentifrices, can reduce S. mutans levels therefore these dentifrices should be indicated for patients with a high risk of caries. However, further study is needed, including antimicrobial analyses against other microbial conditions

Host defense peptides clavanins A and MO reduce in vitro osteoclastogenesis

Aim: Several systemic diseases, such as periodontitis and apical periodontitis, can cause extensive bone resorption. Host defense peptides may have the potential for the development of novel therapies for the bone resorption process. This study evaluated the potential of host defense peptides clavanins A, MO, and LL-37 in in vitro osteoclastogenesis. Methods: RAW 264.7 cultures were stimulated with recombinant of receptor activator of nuclear factor kappa B ligand in the presence of different tested concentrations of host defense peptides, besides calcium hydroxide and doxycycline. Cellular viability, nitric oxide production, and a number of differentiated osteoclast-like cells were also evaluated. Results: Results showed that none of the substances were cytotoxic, except for 128 µg.mL-1 of doxycycline after 3 days. Host defense peptides, calcium hydroxide, and doxycycline did not interfere in nitric oxide production or downregulated it. An exception was observed in the presence of 2 µg.mL-1 of doxycycline, in which nitric oxide production was up-regulated. All host defense peptides were capable of reducing osteoclast-like cell differentiation. Conclusion: Host defense peptides clavanins A and MO demonstrated to be potential suppressors of osteoclastogenesis in vitro without interfering in cellular viability and nitric oxide production. These promising results need to be further analyzed in in vivo models of bone resorption

Concentrated MTA Repair HP reduced biofilm and can cause reparative action at a distance.

AIM: To evaluate in vitro whether MTA Repair HP can induce repair processes at a distance, including its effects on biofilm, cell viability, migration, production of TGF-ß, phosphate and ALP, evaluated through MTA diluted extracts. METHODOLOGY: Initially, antibacterial tests were performed with the bacterium Streptococcus mutans (ATCC 25175) in the presence of MTA extracts (dilutions of 1:1, 1:2 and 1:4). Growth inhibition assay by microdilution in broth, antibiofilm plate assay of young biofilm and antibiofilm assay in confocal microscopy of mature biofilm were carried out. Then, pulp cells were stimulated in the presence of several MTA dilutions, and cell viability (MTT assay), proliferation and migration capacity (scratch assay) were evaluated. To evaluate the capacity of 1:1, 1:2 and 1:4 dilutions of MTA Repair HP to promote the production of important agents of odontogenic differentiation and mineralization, ALP activity, TGF-ß secretion and phosphate quantification were measured. Statistical differences were verified using one-way and two-way anova and Tukey's post-tests. RESULTS: The test dilutions of MTA Repair HP did not inhibit planktonic S. mutans growth but were able to reduce young and mature S. mutans biofilm (p < 0.001). In addition, none of the MTA Repair HP dilutions was cytotoxic for pulp cells. The 1:2 and 1:4 dilutions of MTA Repair HP induced migration and proliferation of pulp cells (p < 0.05). ALP activity and TGF-ß secretion were independent of the tested dilution (p < 0.001). Diluted 1:4 MTA Repair HP produced less phosphate than the more concentrated 1:1 and 1:2 MTA dilutions (p < 0.001). CONCLUSIONS: Undiluted MTA Repair HP reduced S. mutans biofilm, when compared to 1:2 and 1:4 MTA dilutions. Furthermore, none of the tested dilutions was cytotoxic to pulp cells. MTA Repair HP promoted cell migration and proliferation at a distance, assessed through the dilution of the MTA. Even from a distance, MTA Repair HP has the ability to participate in some events related to repair, such as migration, proliferation and TGF production.

Antimicrobial and immunomodulatory in vitro profile of double antibiotic paste.

AIM: To evaluate the antimicrobial and immunomodulatory activity of double antibiotic paste (DAP) in an in vitro infection model. METHODOLOGY: The minimum inhibitory and bactericidal concentrations (MIC and MBC) and the antibiofilm activities (TTC assay) of DAP and its components (ciprofloxacin and metronidazole) were evaluated against Staphylococcus aureus and Enterococcus faecalis compared with triple antibiotic paste (TAP). The cellular viability of RAW 264.7 macrophages (24 and 72 h) and L929 fibroblasts (48 and 72 h) was evaluated by MTT. Furthermore, the production of TNF-α, IL-12, IL-6, IL-1α, IL-10 and NO (on RAW 264.7), besides IL-6, TGF-ß and NO (on L929), stimulated with DAP in baseline and associated with heat-killed microbial-antigen conditions was measured by ELISA and Griess reaction. Data were analysed using the one-way ANOVA test with Bonferroni's corrections. RESULTS: The MBC of pharmacopoeia DAP was similar to TAP for E. faecalis (0.25 µg.  mL-1 ) and lower for S. aureus (DAP 1 µg. mL-1 and TAP 2 µg. mL-1 ; p < .001). Ciprofloxacin was the most effective antibiofilm drug from the pastes (35% of reduction for E. faecalis and S. aureus; p < .0001), and both pastes had a similar antibiofilm eradication against both biofilm species (29% and 35% for S. aureus and 76% and 85% for E. faecalis; p < .0001). DAP was cytotoxic against the tested cells. DAP significantly upregulated IL-1α (p < .001), IL-6 (p < .0001), TNF-α (p < .01) and IL-12 (p < .05; in the absence of antigens) and significantly reduced IL-6 (p < .0001; in the presence of HK-S. aureus) and IL-10 (p < .05; in the presence of both antigens) on macrophages. Furthermore, DAP upregulated IL-6 (p < .001) and NO (p < .05; in the absence of antigens), IL-6 (p < .001; in the presence of HK-S. aureus) and reduced NO (p < .001; in the presence of HK-S. aureus). CONCLUSIONS: Double antibiotic paste and TAP had similar antimicrobial activity against S. aureus and E. faecalis. DAP upregulated pro-inflammatory cytokines mainly in the absence of antigens and had pro- and anti-inflammatory activity in RAW 264.7 macrophages and L929 fibroblasts in the presence of antigens involved in pulp infections.

Salivary function impairment in type 2 Diabetes patients associated with concentration and genetic polymorphisms of chromogranin A.

OBJECTIVES: The purpose of this study was to evaluate the effect of type 2 diabetes mellitus (T2DM) on salivary function impairments according to glycemic control status and subsequently compare the concentration of chromogranin A (CHGA) with its genetic profile. MATERIALS AND METHODS: Thirty-six patients with controlled T2DM, 36 with poorly controlled T2DM, and 38 nondiabetic subjects underwent salivary flow rate measurements by means of unstimulated labial (ULS), unstimulated whole (UWS), and stimulated whole saliva (SWS) collections. CHGA concentrations were determined in saliva and plasma with ELISA, and two CHGA polymorphisms (T-415C and Glu264Asp) were analyzed by polymerase chain reaction-restriction fragment length polymorphism. RESULTS: T2DM patients presented significantly lower ULS and UWS flow rates regardless of glycemic control status compared to controls (P = 0.002 and P = 0.027, respectively). The SWS flow rate in the poorly controlled T2DM was the lowest among the groups (P = 0.026). Significantly higher plasma and salivary CHGA levels were found in T2DM groups (P = 0.019 and P < 0.001, respectively). CHGA gene variants (T-415C and Glu264Asp) revealed significant differences between diabetics and control subjects when associated with lower salivary flow and higher salivary CHGA production (P < 0.05). CONCLUSIONS: T2DM causes abnormalities in the function of salivary glands. However, poorly controlled T2DM has the most influence on SWS flow rates. Our findings indicate an association between plasma and salivary CHGA levels and T2DM patients. Furthermore, the results suggest that CGHA polymorphisms might be associated with salivary gland hypofunction and higher salivary CHGA production in T2DM patients. Nevertheless, further epidemiological studies are required to elucidate this clinical implication. CLINICAL RELEVANCE: Salivary impairments and high levels of CHGA are associated with T2DM patients. In addition, CGHA polymorphisms might be associated with salivary gland hypofunction and higher salivary CHGA production in T2DM patients. This could be a significant insight to establish a role for salivary CHGA as a potential clinical biomarker to T2DM.

Impact of glycemic control on oral health status in type 2 diabetes individuals and its association with salivary and plasma levels of chromogranin A.

OBJECTIVE: To evaluate the effect of glycemic control status in type 2 diabetes mellitus (T2DM) individuals on clinical oral health indicators and to compare the concentrations of plasma and salivary chromogranin A (CHGA) among nondiabetic subjects and T2DM patients, exploring their associations. DESIGN: In this cross-sectional study, 32 patients with controlled T2DM, 31 with poorly controlled T2DM and 37 nondiabetic subjects underwent a clinical and periodontal examination. CHGA concentrations were determined in saliva and plasma with ELISA. RESULTS: Poorly controlled T2DM group exhibited significantly higher mean buffering capacity, plaque index and bleeding on probing than other groups (P<0.05). No difference was found to DMFT (decayed, missed and filled teeth) index between groups. Sites with clinical attachment loss (CAL) of 4 and 5-6mm were significantly higher in both diabetic groups compared to control group (P<0.05). Poorly controlled T2DM group had significantly higher sites with CAL ≥ 7 mm than other groups (P=0.001). Significantly higher plasma and salivary CHGA levels were found in T2DM groups (P<0.05). In both diabetic groups, probing depths 5-6mm and CAL 5-6mm were associated with higher salivary CHGA concentration (P<0.05). CONCLUSIONS: The findings revealed that T2DM patients were more prone to periodontal tissue damage than to caries risk. The results also provide some evidence that the degree of attachment loss deteriorates significantly with poor glycemic control in T2DM (CAL ≥ 7 mm). Moreover, the results suggest that high concentrations of salivary CHGA are associated with worse periodontal parameters and T2DM, and this could be related to the pathogenesis of both diseases.