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1.
Int J Mol Sci ; 22(12)2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-34201389

RESUMO

The objective of this study was to determine reactive oxygen species (ROS) produced by fagopyrin F-rich fraction (FFF) separated from Tartary buckwheat flower extract exposed to lights and to investigate its antibacterial photodynamic inactivation (PDI) against Streptococcus mutans and its biofilm. ROS producing mechanisms involving FFF with light exposure were determined using a spectrophotometer and a fluorometer. S. mutans and its biofilm inactivation after PDI treatment of FFF using blue light (BL; 450 nm) were determined by plate count method and crystal violet assay, respectively. The biofilm destruction by ROS produced from FFF after exposure to BL was visualized using confocal laser scanning microscopy (CLSM) and field emission scanning electron microscope (FE-SEM). BL among 3 light sources produced type 1 ROS the most when applying FFF as a photosensitizer. FFF exposed to BL (5 and 10 J/cm2) significantly more inhibited S. mutans viability and biofilm formation than FFF without the light exposure (p < 0.05). In the PDI of FFF exposed to BL (10 J/cm2), an apparent destruction of S. mutans and its biofilm were observed by the CLSM and FE-SEM. Antibacterial PDI effect of FFF was determined for the first time in this study.


Assuntos
Biofilmes/crescimento & desenvolvimento , Fagopyrum/química , Flores/química , Fármacos Fotossensibilizantes/farmacologia , Extratos Vegetais/farmacologia , Quinonas/farmacologia , Streptococcus mutans/crescimento & desenvolvimento , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Luz , Fotoquimioterapia , Streptococcus mutans/efeitos dos fármacos
2.
Int J Mol Sci ; 22(12)2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34207218

RESUMO

Resin-based composite materials have been widely used in restorative dental materials due to their aesthetic, mechanical, and physical properties. However, they still encounter clinical shortcomings mainly due to recurrent decay that develops at the composite-tooth interface. The low-viscosity adhesive that bonds the composite to the tooth is intended to seal this interface, but the adhesive seal is inherently defective and readily damaged by acids, enzymes, and oral fluids. Bacteria infiltrate the resulting gaps at the composite-tooth interface and bacterial by-products demineralize the tooth and erode the adhesive. These activities lead to wider and deeper gaps that provide an ideal environment for bacteria to proliferate. This complex degradation process mediated by several biological and environmental factors damages the tooth, destroys the adhesive seal, and ultimately, leads to failure of the composite restoration. This paper describes a co-tethered dual peptide-polymer system to address composite-tooth interface vulnerability. The adhesive system incorporates an antimicrobial peptide to inhibit bacterial attack and a hydroxyapatite-binding peptide to promote remineralization of damaged tooth structure. A designer spacer sequence was incorporated into each peptide sequence to not only provide a conjugation site for methacrylate (MA) monomer but also to retain active peptide conformations and enhance the display of the peptides in the material. The resulting MA-antimicrobial peptides and MA-remineralization peptides were copolymerized into dental adhesives formulations. The results on the adhesive system composed of co-tethered peptides demonstrated both strong metabolic inhibition of S. mutans and localized calcium phosphate remineralization. Overall, the result offers a reconfigurable and tunable peptide-polymer hybrid system as next-generation adhesives to address composite-tooth interface vulnerability.


Assuntos
Antibacterianos/química , Cimentos Dentários/química , Proteínas Citotóxicas Formadoras de Poros/química , Antibacterianos/farmacologia , Resinas Compostas/química , Resinas Compostas/farmacologia , Cimentos Dentários/farmacologia , Metacrilatos/química , Proteínas Citotóxicas Formadoras de Poros/farmacologia , Streptococcus mutans/efeitos dos fármacos , Remineralização Dentária/métodos
3.
Biomed Res Int ; 2021: 6692328, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33860052

RESUMO

To investigate the effects of ficin on biofilm formation of conditionally cariogenic Streptococcus mutans (S. mutans). Biomass and metabolic activity of biofilm were assessed using crystal violet assay, colony-forming unit (CFU) counting, and MTT assay. Extracellular polysaccharide (EPS) synthesis was displayed by SEM imaging, bacteria/EPS staining, and anthrone method while acid production was revealed by lactic acid assay. Growth curve and live/dead bacterial staining were conducted to monitor bacterial growth state in both planktonic and biofilm form. Total protein and extracellular proteins of S. mutans biofilm were analyzed by protein/bacterial staining and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), severally. qRT-PCR was conducted to detect acid production, acid tolerance, and biofilm formation associated genes. Crystal violet assay, CFU counting, and MTT assay showed that the suppression effect of ficin on S. mutans biofilm formation was concentration dependent. 4 mg/mL ficin had significant inhibitory effect on S. mutans biofilm formation including biomass, metabolic activity, EPS synthesis, and lactic acid production (p < 0.05). The growth curves from 0 mg/mL to 4 mg/mL ficin were aligned with each other. There was no significant difference among different ficin groups in terms of live/dead bacterial staining result (p > 0.05). Protein/bacterial staining outcome indicated that ficin inhibit both total protein and biofilm formation during the biofilm development. There were more relatively small molecular weight protein bands in extracellular proteins of 4 mg/mL ficin group when compared with the control. Generally, ficin could inhibit biofilm formation and reduce cariogenic virulence of S. mutans effectively in vitro; thus, it could be a potential anticaries agent.


Assuntos
Biofilmes/crescimento & desenvolvimento , Ficina/farmacologia , Streptococcus mutans/fisiologia , Biomassa , Contagem de Colônia Microbiana , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Ácido Láctico/biossíntese , Viabilidade Microbiana/efeitos dos fármacos , Polissacarídeos Bacterianos/biossíntese , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Streptococcus mutans/efeitos dos fármacos , Streptococcus mutans/metabolismo , Streptococcus mutans/ultraestrutura
4.
Carbohydr Polym ; 260: 117777, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33712133

RESUMO

The combination of alginate, hyaluronic acid and multivalent ions have been reported to form alginate-hyaluronic acid ionic-crosslinking hydrogels for biomedical applications. However, injectable alginate-hyaluronic acid ionic-crosslinking hydrogels with satisfactory shear-thinning property have rarely been reported. In this study, we successfully developed an ionic-crosslinked alginate-hyaluronic acid hydrogel by simple assembly of alginate-hyaluronic acid mixture and Fe3+ complex. This hydrogel could fully recover within seconds after damaged, while displayed shear thinning behavior and good injectability which were contributed by the reversible and dynamic metal-ligand interactions formed via ferric ions and carboxyl groups of the polymers. Moreover, the local degradation of this hydrogel giving the hydrogel sustained ferric ions release property, of which led to potential long-term antibacterial activities against multiple types of bacteria including gram-negative Escherichia coli and gram-positive Staphylococcus aureus, as well as representative oral pathogenic bacteria Streptococcus mutans and Porphyromonas gingivalis.


Assuntos
Alginatos/química , Anti-Infecciosos/química , Compostos Férricos/química , Ácido Hialurônico/química , Hidrogéis/química , Animais , Anti-Infecciosos/farmacologia , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Feminino , Compostos Férricos/metabolismo , Humanos , Hidrogéis/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Porphyromonas/efeitos dos fármacos , Reologia , Pele/efeitos dos fármacos , Pele/patologia , Staphylococcus aureus/efeitos dos fármacos , Streptococcus mutans/efeitos dos fármacos
5.
Nutrients ; 13(3)2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33668205

RESUMO

The potent antimicrobial effects of antimicrobial photodynamic therapy (aPDT) with visible light plus water-filtered infrared-A irradiation and natural compounds as photosensitizers (PSs) have recently been demonstrated. The aim of this study was to obtain information on the antimicrobial effects of aPDT with mother juices against typical cariogenic oral Streptococcus pathogens in their planktonic form and determine its eradication potential on total human salivary bacteria from volunteers. Mother juices of pomegranate, bilberry, and chokeberry at different concentrations were used as PSs. The unweighted (absolute) irradiance was 200 mW cm-2, applied five minutes. Planktonic cultures of Streptococcus mutans and Streptococcus sobrinus and total mixed bacteria from pooled saliva of volunteers were treated with aPDT. Up to more than 5 log10 of S. mutans and S. sobrinus were killed by aPDT with 0.4% and 0.8% pomegranate juice, 3% and 50% chokeberry juice, and 12.5% bilberry juice (both strains). Concentrations of at least 25% (pomegranate) and >50% (chokeberry and bilberry) eradicated the mixed bacteria in saliva samples. This pilot study has shown that pomegranate mother juice is superior to the berry juices as a multicomponent PS for killing pathogenic oral bacteria with aPDT.


Assuntos
Antibacterianos/farmacologia , Sucos de Frutas e Vegetais/análise , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Saliva/microbiologia , Humanos , Luz , Photinia/química , Projetos Piloto , Romã (Fruta)/química , Streptococcus mutans/efeitos dos fármacos , Streptococcus sobrinus/efeitos dos fármacos , Vaccinium myrtillus/química
6.
J Infect Public Health ; 14(3): 324-330, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33618277

RESUMO

BACKGROUND: Streptococcus mutans are an oral pathogen that causes dental caries, endocarditis, and systemic dysfunctions, an alternative antibacterial solution from silver nanoparticles (AgNPs) are investigated. METHODS: AgNPs were synthesized using the ethnobotanical product gum Arabic. It influenced the nanoparticles with medicinal value through their role as capping, stabilizing, or surface-attached components. The biophysical characteristics of the synthesized AgNPs were studied using UV-vis spectrum, XRD, EDAX, SEM, and TEM tools. The AgNPs were spherical with the average size less than 10 nm. By using the well diffusion and microdilution techniques, the impact of synthesized AgNPs was tested against S. mutans isolates. RESULTS: The smaller the size, the greater the antibacterial and antiviral potential the particles exhibit. The biophysical characteristics of AgNPs the presence of phenols, alcohols, amides, sulfoxide, flavanoids, terpenoids and steroids. The AgNPs exhibited a good antibacterial action against the oral pathogen S. mutans. The synthesized NPs at a dose level of 200 µg/mL exhibited an inhibition zone with 18.30 ± 0.5 nm diameter. The synthesised nanoparticles inhibited the genes responsible for biofilm formation of S. mutans over host tooth and gums (gtfB, gtfc, gtfD) and virulent protective factors (comDE, brpA and smu 360) and survival promoter genes (gyrA and spaP, gbpB). CONCLUSION: The potent antibiotic action over S. mutans seen with the synthesized NPs, paves the way for the development of novel dental care products. Also, the small-sized NPs promote its applicability in COVID-19 pandemic containment.


Assuntos
Antibacterianos/farmacologia , Cárie Dentária/tratamento farmacológico , Endocardite/tratamento farmacológico , Nanopartículas Metálicas , Prata/farmacologia , Streptococcus mutans/efeitos dos fármacos , Biofilmes , Goma Arábica , Humanos
7.
Molecules ; 26(3)2021 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-33572576

RESUMO

Postbiotics are a promising functional ingredient that can overcome the limitations of viability and storage stability that challenge the production of probiotics. To evaluate the effects of postbiotics on oral health, eight spent culture supernatants (SCSs) of probiotics were prepared, and the effects of SCSs on Streptococcus mutans-induced cariogenic biofilm formation and the receptor activator of the nuclear factor κB ligand (RANKL)-induced osteoclastogenesis were evaluated in RAW 264.7 macrophages. SCS of Lactobacillus salivarius MG4265 reduced S. mutans-induced biofilm formation by 73% and significantly inhibited tartrate-resistant acid phosphatase (TRAP) activity, which is a biomarker of mature osteoclasts in RAW 264.7 macrophages. The suppression of RANKL-induced activation of mitogen activated the protein kinases (c-Jun N-terminal kinase, extracellular signal-regulated kinase, and p38) and nuclear factor κB pathways, as well as the upregulation of heme oxygenase-1 expression. The suppression of RANK-L-induced activation of mitogen also inhibited the expression of transcriptional factors (c-fos and nuclear factor of activated T cells cytoplasmic 1) and, subsequently, osteoclastogenesis-related gene expression (tartrate-resistant acid phosphatase-positive (TRAP), cathepsin K, and matrix metalloproteinase-9).Therefore, SCS of L. salivarius MG4265 has great potential as a multifunctional oral health ingredient that inhibits biofilm formation and suppresses the alveolar bone loss that is associated with periodontitis.


Assuntos
Biofilmes/efeitos dos fármacos , Lactobacillus salivarius/crescimento & desenvolvimento , Macrófagos/citologia , Osteoclastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Probióticos/farmacologia , Streptococcus mutans/fisiologia , Animais , Biofilmes/crescimento & desenvolvimento , Diferenciação Celular/efeitos dos fármacos , Heme Oxigenase-1/metabolismo , Proteínas de Membrana/metabolismo , Camundongos , Osteoclastos/citologia , Ligante RANK/farmacologia , Células RAW 264.7 , Streptococcus mutans/efeitos dos fármacos
8.
Arch Oral Biol ; 122: 105022, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33418434

RESUMO

The objective of this study was to perform a comprehensive review of the use of antimicrobial peptides for the prevention and treatment of dental caries. The study included publications in the English language that addressed the use of antimicrobial peptides in the prevention and treatment of caries. These publications were also searchable on PubMed, Web of Science, Embase, Scopus, the Collection of Anti-Microbial Peptides and the Antimicrobial Peptide Database. A total of 3,436 publications were identified, and 67 publications were included. Eight publications reported seven natural human antimicrobial peptides as bactericidal to Streptococcus mutans. Fifty-nine publications reported 43 synthetic antimicrobial peptides developed to mimic natural antimicrobial peptides, fusing peptides with functional sequences and implementing new designs. The 43 synthetic antimicrobial peptides were effective against Streptococcus mutans, and nine peptides specifically targeted Streptococcus mutans. Ten antimicrobial peptides had an affinity for hydroxyapatite to prevent bacterial adhesion. Six antimicrobial peptides were also antifungal. Four antimicrobial peptides promoted remineralisation or prevented the demineralisation of teeth by binding calcium to hydroxyapatite. In conclusion, this study identified 67 works in the literature that reported seven natural and 43 synthetic antimicrobial peptides for the prevention and treatment of caries. Most of the antimicrobial peptides were bactericidal, and some prevented bacterial adhesion. A few antimicrobial peptides displayed remineralising properties with hydroxyapatite.


Assuntos
Antibacterianos/uso terapêutico , Cárie Dentária , Proteínas Citotóxicas Formadoras de Poros/uso terapêutico , Aderência Bacteriana/efeitos dos fármacos , Biofilmes , Cárie Dentária/tratamento farmacológico , Cárie Dentária/prevenção & controle , Durapatita , Humanos , Streptococcus mutans/efeitos dos fármacos , Remineralização Dentária
9.
Arch Oral Biol ; 122: 105032, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33418435

RESUMO

OBJECTIVES: This study aims to investigate the effects of tea extracts on biofilm formation by oral streptococci and the potential mechanisms behind the effects. DESIGN: We examined the effects of five types of tea extracts (green, oolong, black, pu-erh and chrysanthemum tea) on cell surface hydrophobicity and auto-aggregation of three different streptococcal species (Streptococcus mutans, Streptococcus salivarius and Streptococcus mitis) and evaluated their biofilm formation on four disparate hard surfaces (glass, stainless steel, hydroxyapatite and titanium). The correlation between biofilm formation and the cellular properties were investigated in order to study the mechanisms by which the tea extracts affect biofilm formation. RESULTS: Results show that the tea extracts reduced cell surface hydrophobicity (by up to 57.9 %) and, in some cases, altered cellular auto-aggregation (by up to 12 %) and biofilm formation (by up to 2.61 log CFU cm-2). Specifically, oolong tea extract was found to enhance biofilm formation by increasing cellular auto-aggregation and pu-erh tea extract retarded biofilm formation by increasing auto-aggregation. Biofilm formation correlated well to cell surface hydrophobicity and auto-aggregation in combination, but not to either one alone as determined by multiple linear regression analysis. CONCLUSIONS: Tea extracts have the ability to modulate streptococcal biofilm formation by altering cell surface hydrophobicity and cellular aggregation.


Assuntos
Biofilmes/efeitos dos fármacos , Extratos Vegetais/farmacologia , Streptococcus mutans/efeitos dos fármacos , Chá/química , Durapatita , Vidro , Interações Hidrofóbicas e Hidrofílicas , Aço Inoxidável , Titânio
10.
Int J Mol Sci ; 22(1)2021 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-33401545

RESUMO

Poly(methyl methacralyate) (PMMA) has long been used in dentistry as a base polymer for dentures, and it is recently being used for the 3D printing of dental materials. Despite its many advantages, its susceptibility to microbial colonization remains to be overcome. In this study, the interface between 3D-printed PMMA specimens and oral salivary biofilm was studied following the addition of zwitterionic materials, 2-methacryloyloxyethyl phosphorylcholine (MPC) or sulfobetaine methacrylate (SB). A significant reduction in bacterial and biofilm adhesions was observed following the addition of MPC or SB, owing to their protein-repellent properties, and there were no significant differences between the two test materials. Although the mechanical properties of the tested materials were degraded, the statistical value of the reduction was minimal and all the properties fulfilled the requirements set by the International Standard, ISO 20795-2. Additionally, both the test materials maintained their resistance to biofilm when subjected to hydrothermal fatigue, with no further deterioration of the mechanical properties. Thus, novel 3D-printable PMMA incorporated with MPC or SB shows durable oral salivary biofilm resistance with maintenance of the physical and mechanical properties.


Assuntos
Materiais Biocompatíveis/farmacologia , Biofilmes/efeitos dos fármacos , Resinas Compostas/química , Materiais Dentários/farmacologia , Boca/efeitos dos fármacos , Polímeros/química , Impressão Tridimensional/instrumentação , Aderência Bacteriana , Biofilmes/crescimento & desenvolvimento , Humanos , Teste de Materiais , Metacrilatos/química , Boca/microbiologia , Fosforilcolina/análogos & derivados , Fosforilcolina/química , Streptococcus mutans/efeitos dos fármacos , Streptococcus mutans/metabolismo
11.
Int J Biol Macromol ; 173: 99-108, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33460660

RESUMO

The present investigation reports an in-vitro study using combination of laccase and an enhancer capable of inhibiting the growth of pathogenic microorganisms, preventing biofilm formation, and whitening teeth. Laccase-cinnamic acid system remarkably inhibited the growth of Aggregatibacter actinomycetemcomitans, Candida albicans, S. aureus, and Streptococcus mutans whilst showed no significant effects on Gram-negative bacteria. Data presented that cinnamic acid (10 mM) with laccase (0.125 U ml-1) led to a maximum decrease of about 90%, in S. mutans biofilm formation. The confocal laser scanning microscopy showed considerable detachment of S. mutans cells from glass substratum. The combined laccase-cinnamic acid system could remove teeth discoloration caused by coffee. SEM of the teeth surface exhibited no damages such as surface cracking or fracture. Liquid chromatography-tandem mass spectrometry (LC-MS) and cyclic voltammetry (CV) studies showed that laccase can catalyze the one-electron oxidation of cinnamic acid to the respective radical. This radical can then undergo several fates, including recombination with another radical to form a dimeric species, dismutation of the radical back to cinnamic acid or decarboxylation to give various reduced oxygen species. Therefore, the redox potential values of phenolic monomers/oligomers are related with their biological activities.


Assuntos
Aggregatibacter actinomycetemcomitans/efeitos dos fármacos , Antibacterianos/farmacologia , Cinamatos/farmacologia , Proteínas Fúngicas/farmacologia , Hericium/química , Lacase/farmacologia , Aggregatibacter actinomycetemcomitans/crescimento & desenvolvimento , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Ácidos Cafeicos/farmacologia , Candida albicans/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Catecóis/farmacologia , Sinergismo Farmacológico , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Proteínas Fúngicas/isolamento & purificação , Ácido Gálico/farmacologia , Hericium/enzimologia , Hidroquinonas/farmacologia , Lacase/isolamento & purificação , Lactobacillus/efeitos dos fármacos , Lactobacillus/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Oxirredução , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/crescimento & desenvolvimento , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Streptococcus mutans/efeitos dos fármacos , Streptococcus mutans/crescimento & desenvolvimento , Clareadores Dentários/farmacologia
12.
J Appl Microbiol ; 130(2): 382-393, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32707601

RESUMO

AIMS: The aim of this study was to investigate the effects of trans-cinnamaldehyde (TC) and its synergistic activity with chlorhexidine (CHX) and fluoride against Streptococcus mutans. METHODS AND RESULTS: Streptococcus mutans UA159 was treated with TC alone and in combination with CHX or sodium fluoride. The synergy profile was analysed using the Zero Interaction Potency model. TC showed strong synergism (synergy score of 21·697) with CHX, but additive effect (synergy score of 5·298) with fluoride. TC and the combinations were tested for acid production (glycolytic pH drop) and biofilm formation by S. mutans, and nitric oxide production in macrophages. TC significantly inhibited sucrose-dependent biofilm formation and acid production by S. mutans. Mechanistic studies were carried out by qRT-PCR-based transcriptomic studies which showed that TC acts by impairing genes related to metabolism, quorum sensing, bacteriocin expression, stress tolerance and biofilm formation. CONCLUSIONS: trans-Cinnamaldehyde potentiates CHX and sodium fluoride in inhibiting S. mutans biofilms and virulence through multiple mechanisms. This study sheds significant new light on the potential to develop TC as an anti-caries treatment. SIGNIFICANCE AND IMPACT OF THE STUDY: Oral diseases were classified as a 'silent epidemic' in the US Surgeon General's Report on Oral Health. Two decades later, >4 billion people are still affected worldwide by caries, having significant effects on the quality of life. There is an urgent need to develop novel compounds and strategies to combat dental caries. Here, we prove that TC downregulates multiple pathways and potentiates the CHX and fluoride to prevent S. mutans biofilms and virulence. This study sheds significant new light on the potential to develop TC in combination with CHX or fluoride as novel treatments to arrest dental caries.


Assuntos
Acroleína/análogos & derivados , Cariostáticos/farmacologia , Clorexidina/farmacologia , Fluoreto de Sódio/farmacologia , Streptococcus mutans/efeitos dos fármacos , Acroleína/farmacologia , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Sinergismo Farmacológico , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Humanos , Streptococcus mutans/crescimento & desenvolvimento , Streptococcus mutans/metabolismo , Virulência/efeitos dos fármacos , Virulência/genética
13.
Arch Oral Biol ; 122: 105024, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33352361

RESUMO

OBJECTIVE: We evaluated the effect of antimicrobial photodynamic therapy (a-PDT) with Rose Bengal and blue light LED on bacteria that initiate and promote dental caries. DESIGN: Colony forming units of Streptococcus mutans, Streptococcus sobrinus, Streptococcus sanguinis, and Lactobacillus salivarius under planktonic and biofilm conditions were counted after a-PDT treatment using Rose Bengal and blue light LED. In addition, cariogenic bacteria from saliva and dental plaques from ten volunteers were used for evaluation of a-PDT treatment. RESULTS: We found that a-PDT using Rose Bengal at > 10 µg/mL had antimicrobial effects on oral Gram-positive S. mutans, S. sobrinus, S. sanguinis, and L. salivarius under both planktonic and biofilm conditions. The effect was also observed for cariogenic bacteria that formed biofilms containing water-insoluble glucans, through which the bacteria are firmly attached to the tooth surface. Moreover, a-PDT led to a marked reduction in cariogenic bacteria in saliva and dental plaques. CONCLUSION: a-PDT could be a useful approach for controlling dental caries in dental surgery.


Assuntos
Anti-Infecciosos , Fotoquimioterapia , Rosa Bengala/farmacologia , Streptococcus mutans/efeitos dos fármacos , Streptococcus mutans/efeitos da radiação , Anti-Infecciosos/farmacologia , Biofilmes/efeitos dos fármacos , Biofilmes/efeitos da radiação , Cárie Dentária/tratamento farmacológico , Humanos
14.
Molecules ; 25(23)2020 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-33291521

RESUMO

In our previous study, temporin-GHaR (GHaR) showed potent antimicrobial activity with strong hemolytic toxicity. To overcome its weakness, we designed GHaR6R, GHaR7R, GHaR8R, GHaR9R, and GHaR9W by changing the number of positive charges and the hydrophobic surface of GHaR. With the exception of GHaR7R, the hemolytic toxicity of the derived peptides had been reduced, and the antimicrobial activities remained close to the parent peptide (except for GHaR9R). GHaR6R, GHaR7R, GHaR8R, and GHaR9W exhibited a great bactericidal effect on Streptococcus mutans (S. mutans), which is one of the main pathogens causing dental caries. According to the membrane permeation and scanning electron microscope (SEM) analysis, these derived peptides targeted to the cell membranes of planktonic bacteria, contributing to the disruption of the membrane integrity and leakage of the intracellular contents. Moreover, they inhibited the formation of biofilms and eradicated the mature biofilms of S. mutans. Compared with GHaR7R, the derived peptides showed less cytotoxicity to human oral epithelial cells (HOECs). The derived peptides are expected to be the molecular templates for designing antibacterial agents to prevent dental caries.


Assuntos
Anti-Infecciosos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Biofilmes/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Peptídeos/farmacologia , Streptococcus mutans/efeitos dos fármacos , Membrana Celular/microbiologia , Cárie Dentária/microbiologia , Células Epiteliais/microbiologia , Eritrócitos/microbiologia , Humanos , Testes de Sensibilidade Microbiana/métodos
15.
Int J Mol Sci ; 21(24)2020 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-33322170

RESUMO

Streptococcus mutans (S. mutans) is widely regarded as the main cause of human dental caries via three main virulence factors: adhesion, acidogenicity, and aciduricity. Citric acid is one of the antibiotic agents that can inhibit the virulence capabilities of S. mutans. A full understanding of the acidic resistance mechanisms (ARMs) causing bacteria to thrive in citrate transport is still elusive. We propose atomic force microscopy (AFM) equipped with a fluid cell to study the S. mutans ARMs via surface nanomechanical properties at citric acid pH 3.3, 2.3, and 1.8. Among these treatments, at pH 1.8, the effect of the citric acid shock in cells is demonstrated through a significantly low number of high adhesion zones, and a noticeable reduction in adhesion forces. Consequently, this study paves the way to understand that S. mutans ARMs are associated with the variation of the number of adhesion zones on the cell surface, which is influenced by citrate and proton transport. The results are expected to be useful in developing antibiotics or drugs involving citric acid for dental plaque treatment.


Assuntos
Biofilmes/efeitos dos fármacos , Ácido Cítrico/farmacologia , Microscopia de Força Atômica/instrumentação , Microscopia de Força Atômica/métodos , Streptococcus mutans/efeitos dos fármacos , Virulência/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Adesão Celular/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Impressão Tridimensional , Propriedades de Superfície , Fatores de Virulência
16.
ACS Appl Mater Interfaces ; 12(49): 54497-54506, 2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33226209

RESUMO

Periodontitis is a bacterial infectious disease leading to the loss of periodontal supporting tissues and teeth. The current guided tissue regeneration (GTR) membranes for periodontitis treatments cannot effectively promote tissue regeneration for the limited antibacterial properties and the excessively fast degradation rate. Besides, they need extra tailoring according to variform defects before implantation, leading to imprecise match. This study proposed an injectable sodium alginate hydrogel composite (CTP-SA) doped with cubic cuprous oxide (Cu2O) and polydopamine-coated titanium dioxide (TiO2@PDA) nanoparticles for GTR. Inspired by the gelation process of the jelly, the phase change (liquid to solid) of CTP-SA after injection could automatch variform bone defects. Meanwhile, CTP-SA exhibited broad-spectrum antibacterial capabilities under blue light (BL) irradiation, including Streptococcus mutans (one of the most abundant bacteria in oral biofilms). Moreover, the reactive oxygen species released under BL excitation could accelerate the oxidation of Cu+ to Cu2+. Afterward, osteogenesis could be enhanced through two factors simultaneously: the stimulation of newly formed Cu2+ and the photothermal effect of CTP-SA under near-infrared (NIR) irradiation. Collectively, through this dual-light (blue and NIR) noninvasive regulation, CTP-SA could switch antibacterial and osteogenic modes to address requirements of patients at different healing stages, thereby realizing the customized GTR procedures.


Assuntos
Antibacterianos/química , Materiais Biocompatíveis/química , Nanopartículas/química , Alginatos/química , Animais , Antibacterianos/farmacologia , Materiais Biocompatíveis/farmacologia , Biofilmes/efeitos dos fármacos , Regeneração Óssea/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Cobre/química , Hidrogéis/química , Indóis/química , Raios Infravermelhos , Luz , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Nanopartículas/toxicidade , Osteogênese/efeitos dos fármacos , Polímeros/química , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/química , Espécies Reativas de Oxigênio/metabolismo , Streptococcus mutans/efeitos dos fármacos , Streptococcus mutans/fisiologia , Titânio/química
17.
Niger J Clin Pract ; 23(11): 1578-1582, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33221785

RESUMO

Aims: The authors have used an in vitro model to appraise the antimicrobial efficacy of diode lasers with two different power outputs on Streptococcus mutans (SM), Lactobacillus casei (LC), and Actinomyces naeslundii (AN). Methods and Materials: The coronal dentin of thirty human mandibular third molars was prepared with four cylindrical cavities left in contact with SM, LC, and AN for 72 h to facilitate bacterial penetration. Diode laser (810 nm for 30 s in two cycles) with 1.5 W (group I), 1 W (group II), and 2% chlorhexidine gluconate solution for 60 s (group III) was applied on three cavities and the fourth cavity was not subjected to any treatment (control). Similar amounts of dentin debris were collected from the cavity into sterile tubes. The bacterial count was determined by serial dilution and plate count method. Percentage of killing was calculated for comparative analysis. Results: The percentage of SM killed after exposure was 73.68 ± 23.37, 51.75 ± 25.45, and 26.78 ± 21.8 in three groups, respectively, (P = 0.002; Kruskal-Wallis) with no significant difference between group I and group II (P = 0.089; Mann-Whitney). The percentage of AN killed after exposure was 37.77 ± 49.52, 22 ± 19.48, and 56.86 ± 23.93 in three groups, respectively, (P = 0.013; Kruskal-Wallis) with significant difference between group II and group III (P = 0.002; Mann-Whitney). The percentage of LC killed after exposure was 51.32 ± 39.07, 36.65 ± 38.48, and 75.41 ± 22.6 in three groups, respectively (P = 0.091; Kruskal-Wallis). Conclusions: Diode lasers exerted antibacterial effect of varying levels against all the three cariogenic bacteria. Although they are recommended as a supplementary antibacterial surface pretreatment technique for efficient removal of cariogenic bacteria, further clinical studies are required to confirm the in vitro findings.


Assuntos
Actinomyces/efeitos dos fármacos , Antibacterianos/farmacologia , Cárie Dentária/microbiologia , Dentina/microbiologia , Lactobacillus casei/efeitos dos fármacos , Lasers Semicondutores/uso terapêutico , Preparo da Cavidade Dentária , Humanos , Técnicas In Vitro , Terapia a Laser , Streptococcus mutans/efeitos dos fármacos
18.
World J Microbiol Biotechnol ; 36(12): 189, 2020 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-33242145

RESUMO

The purpose of this study was to develop a rapid and simple measurement method for biofilm formation inhibitory activity, and to screen food additives and foodstuffs that inhibit biofilm formation. The measurement method for biofilm formation inhibitory activity was developed by combining biofilm formation on pins of microtiter plate lids and staining using crystal violet. The optimum conditions for biofilm formation on the pins were established for seven Gram-positive and six Gram-negative bacteria by investigations of media, incubation time, and pin materials. Minimum concentrations of food additives required to inhibit biofilm formation were determined using the proposed method. The values obtained by the proposed and conventional methods agreed well. In addition, by sequential measurements of minimum inhibitory concentrations and minimum bactericidal concentrations using the proposed method, mechanisms of inhibition of biofilm formation were assessed. Furthermore, inhibitory activities of the water extracts of 498 different plant foodstuffs on biofilm formation by Streptococcus mutans were measured; five of the extracts showed potent inhibitory activities. The method proposed here circumvents the tedious and time-consuming conventional method in which biofilms are cultivated on the bottom of wells of microtiter plates.


Assuntos
Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Biofilmes/crescimento & desenvolvimento , Aditivos Alimentares/farmacologia , Testes de Sensibilidade Microbiana/métodos , Meios de Cultura , Coloração e Rotulagem/métodos , Streptococcus mutans/efeitos dos fármacos , Streptococcus mutans/crescimento & desenvolvimento
19.
Int J Nanomedicine ; 15: 8759-8766, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33204086

RESUMO

Introduction: The aim of this study was to clinically evaluate Streptococcus mutans adhesion on titanium dioxide-coated stainless steel orthodontic wires to decrease white-spot formation. Methods: In this study, four groups of 17 patients each (n=68) aged 12-25 years participated. A titanium dioxide coating layer was deposited on 0.4572 mm stainless steel orthodontic wires using physical vapor deposition. The coated wires were randomly assigned to one jaw, and the opposite jaw received an uncoated wire as control. Patients were divided into groups according to the duration that wires were in their mouths: A) 1 week, B) 2 weeks, C) 3 weeks, and D) 4 weeks. Block randomization was used to assign patients to each group. At the end of the experiment, 20 mm of each wire (canine-to-canine area) was cut and cultured in S. mutans-specific medium. The culture plates were placed in an incubator containing 5% CO2 for 72 hours at 37°C, and then colonies were counted. MTT was used to test the biocompatibility of the coated and uncoated wires. To evaluate the stability of the coated titanium dioxide layer on the wires, titanium concentration on the saliva was determined using inductively coupled plasma mass spectroscopy. Results: The Kruskal-Wallis test showed that there was no significant difference in colony counts among the coated wires during 1-4 weeks (p<0.48). In the uncoated-wire groups, colonys count at week 1 were higher than weeks 24 -(p<0.022). Wilcoxon's test showed that the number of colonies was significantly different in groups A and C, but there was no significant difference in groups B or D. MTT-assay results showed that there was not a significant difference between cell viability in the coated-wire group and the control. The Kruskal-Wallis test showed that there was no significant difference in titanium concentration in the studied groups (p<0.834). Conclusion: Application of titanium dioxide coating is effective in reducing bacterial adhesion at wire insertion.


Assuntos
Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Fios Ortodônticos/microbiologia , Aço Inoxidável/química , Streptococcus mutans/efeitos dos fármacos , Titânio/química , Titânio/farmacologia , Adolescente , Adulto , Animais , Aderência Bacteriana/efeitos dos fármacos , Criança , Cães , Humanos , Teste de Materiais , Streptococcus mutans/fisiologia , Propriedades de Superfície , Adulto Jovem
20.
Mol Oral Microbiol ; 35(6): 260-270, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33000897

RESUMO

Fluoride has been used as an effective anticaries agent for more than 70 years, which might result in the emergence of fluoride-resistant strains. However, the fluoride resistance mechanism and the cariogenic properties of fluoride-resistant mutant for cariogenic bacterial species Streptococcus mutans remain largely unknown. We describe here the construction and characterization of a mariner-based transposon system designed to be used in S. mutans, which is also potentially applicable to other streptococci. To identify genetic determinants of fluoride resistance in S. mutans, we constructed a library of S. mutans transposon insertion mutants and screened this library to identify mutants exhibiting fluoride resistance phenotype. Two mutants were found to carry transposon insertion in two different genetic loci (smu.396 and smu.1291c), respectively. Our subsequent genetic study indicates the fluoride-resistant phenotype for the mutant with the insertion in smu.1291c is resulting from the constitutive overexpression of downstream operon smu.1290c-89c, which is consistent with the previous reports. We also demonstrate for the first time that the deletion of smu.396 is responsible for the fluoride-resistant phenotype and that the combining of smu1290c-89c overexpression and smu.396 deletion in one strain could attribute an additive effect on the fluoride resistance. In addition, our results suggest that the biological fitness of those fluoride-resistant mutants is reduced compared to that of wild-type strain. Overall, our identification and characterization of genetic determinants responsible for fluoride resistance in S. mutans expand our understanding of the fluoride resistance mechanism and the biological consequence of the fluoride resistance strains.


Assuntos
Proteínas de Bactérias/genética , Fluoretos , Streptococcus mutans , Elementos de DNA Transponíveis , Fluoretos/farmacologia , Biblioteca Gênica , Mutagênese Insercional , Óperon , Streptococcus mutans/efeitos dos fármacos , Streptococcus mutans/genética
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