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International Journal of Nanomedicine 2024To investigate the inhibition of Streptococcus mutans (S.mutans) and its biofilm by AgBr-nanoparticles (NP) @CTMAB (cetyltrimethyl-ammonium bromide) and evaluate the...
PURPOSE
To investigate the inhibition of Streptococcus mutans (S.mutans) and its biofilm by AgBr-nanoparticles (NP) @CTMAB (cetyltrimethyl-ammonium bromide) and evaluate the changes in Polymethyl methacrylate (PMMA)'s surface roughness (Ra), microhardness, and flexural strength during prolonged immersion in AgBr-NP@CTMAB for application in the denture cleaning industry.
PATIENTS AND METHODS
The antibacterial activity of AgBr-NP@CTMAB against S.mutans was measured colony formation assay, OD600 and laser confocal microscopy. Changes in the specimens' values for surface roughness, microhardness, and flexural strength (MPa) were measured after immersion solutions for 180 or 360 days.
RESULTS
The AgBr-NP@CTMAB solution exhibited a robust antibacterial effect on planktonic S. mutans, with a minimum bactericidal concentration of 5 µg/mL. The 10 µg/mL AgBr-NP@CTMAB solution efficiently inhibited S. mutans biofilm formation. (2) No significant difference in surface roughness after immersion in AgBr-NP@CTMAB (10 µg/mL and 20 µg/mL) comparing with distilled water (P > 0.05) and Polident had significantly higher than distilled water (P < 0.05). There was a significant decrease in the surface hardness of the PMMA specimens that were immersed in the Polident compared with those in distilled water (P < 0.05). While, no significant differences in surface hardness after immersion in the AgBr-NP@CTMAB (P > 0.05). The result of flexural strength suggested that there was no statistically significant difference (P < 0.05) between AgBr-NP@CTMAB as well as Polident and water.
CONCLUSION
AgBrNP@CTMAB can efficiently inhibit the growth of plankton S.mutans and biofilm formation, without affecting the flexural strength, microhardness, or surface roughness of PMMA. Therefore, AgBrNP@CTMAB holds promise as a new denture cleaning agent.
Topics: Polymethyl Methacrylate; Hardness; Flexural Strength; Streptococcus mutans; Denture Bases; Nanoparticles; Water; Anti-Bacterial Agents; Surface Properties; Materials Testing; Borates; Sulfates
PubMed: 38348176
DOI: 10.2147/IJN.S436613 -
Frontiers in Cellular and Infection... 2024Improved understanding of throat colonization in the presence of other co-existing microbes is important for mapping adaptation to the human throat, and recurrence of...
INTRODUCTION
Improved understanding of throat colonization in the presence of other co-existing microbes is important for mapping adaptation to the human throat, and recurrence of infection. Here, we explore the responses triggered by the encounter between two common throat bacteria, and , to identify genes in that are important for colonization in the presence of human tonsillar epithelial cells and , and further compare this transcriptome with the genes expressed in as only bacterium.
METHODS
We performed an co-culture experiment followed by RNA sequencing to identify interaction-induced transcriptional alterations and differentially expressed genes (DEGs), followed by gene enrichment analysis.
RESULTS AND DISCUSSION
A total of 332 and 279 significantly differentially expressed genes with p-value < 0.05 and log FoldChange (logFC) ≥ |2| were identified in after 1 h and 3 h co-culturing, respectively. Alterations in expression of various survival factors were observed when co-cultured with and tonsillar cells. The serine-aspartate repeat-containing protein D () involved in adhesion, was for example highly upregulated in during co-culturing with compared to grown in the absence of , especially at 3 h. Several virulence genes encoding secreted proteins were also highly upregulated only when was co-cultured with and tonsillar cells, and iron does not appear to be a limiting factor in this environment. These findings may be useful for the development of interventions against throat colonization and could be further investigated to decipher the roles of the identified genes in the host immune response in context of a throat commensal landscape.
Topics: Humans; Staphylococcus aureus; Transcriptome; Streptococcus anginosus; Coculture Techniques; Staphylococcal Infections
PubMed: 38333035
DOI: 10.3389/fcimb.2024.1326730 -
MSphere Feb 2024The bacteria within supragingival biofilms participate in complex exchanges with other microbes inhabiting the same niche. One example is the mutans group streptococci...
UNLABELLED
The bacteria within supragingival biofilms participate in complex exchanges with other microbes inhabiting the same niche. One example is the mutans group streptococci (s), implicated in the development of tooth decay, and other health-associated commensal streptococci species. Previously, our group transcriptomically characterized intermicrobial interactions between and several species of oral bacteria. However, these experiments were carried out in a medium without human saliva. To better mimic their natural environment, we first evaluated how inclusion of saliva affected growth and biofilm formation of eight species individually and found saliva to positively benefit growth rates while negatively influencing biofilm biomass accumulation and altering spatial arrangement. These results carried over during evaluation of 29 saliva-derived isolates of various species. Surprisingly, we also found that addition of saliva increased the competitive behaviors of in coculture competitions against commensal streptococci that led to increases in biofilm microcolony volumes. Through transcriptomically characterizing mono- and cocultures of and with and without saliva, we determined that each species developed a nutritional niche under mixed-species growth, with upregulating carbohydrate uptake and utilization pathways while upregulated genome features related to peptide uptake and glycan foraging. also upregulated genes involved in oxidative stress tolerance, particularly manganese uptake, which we could artificially manipulate by supplementing in manganese leading to an advantage over its opponent. Our report highlights observable changes in microbial behaviors through leveraging environmental- and host-supplied resources over their competitors.
IMPORTANCE
Dental caries (tooth decay) is the most prevalent disease for both children and adults nationwide. Caries are initiated from demineralization of the enamel due to organic acid production through the metabolic activity of oral bacteria growing in biofilm communities attached to the tooth's surface. Mutans group streptococci are closely associated with caries development and initiation of the cariogenic cycle, which decreases the amount of acid-sensitive, health-associated commensal bacteria while selecting for aciduric and acidogenic species that then further drives the disease process. Defining the exchanges that occur between mutans group streptococci and oral commensals in a condition that closely mimics their natural environment is of critical need toward identifying factors that can influence odontopathogen establishment, persistence, and outgrowth. The goal of our research is to develop strategies, potentially through manipulation of microbial interactions characterized here, that prevent the emergence of mutans group streptococci while keeping the protective flora intact.
Topics: Child; Humans; Saliva; Competitive Behavior; Dental Caries; Manganese; Streptococcus; Streptococcus mutans; Biofilms
PubMed: 38319113
DOI: 10.1128/msphere.00771-23 -
Cell Feb 2024Streptococcus anginosus (S. anginosus) was enriched in the gastric mucosa of patients with gastric cancer (GC). Here, we show that S. anginosus colonized the mouse...
Streptococcus anginosus (S. anginosus) was enriched in the gastric mucosa of patients with gastric cancer (GC). Here, we show that S. anginosus colonized the mouse stomach and induced acute gastritis. S. anginosus infection spontaneously induced progressive chronic gastritis, parietal cell atrophy, mucinous metaplasia, and dysplasia in conventional mice, and the findings were confirmed in germ-free mice. In addition, S. anginosus accelerated GC progression in carcinogen-induced gastric tumorigenesis and YTN16 GC cell allografts. Consistently, S. anginosus disrupted gastric barrier function, promoted cell proliferation, and inhibited apoptosis. Mechanistically, we identified an S. anginosus surface protein, TMPC, that interacts with Annexin A2 (ANXA2) receptor on gastric epithelial cells. Interaction of TMPC with ANXA2 mediated attachment and colonization of S. anginosus and induced mitogen-activated protein kinase (MAPK) activation. ANXA2 knockout abrogated the induction of MAPK by S. anginosus. Thus, this study reveals S. anginosus as a pathogen that promotes gastric tumorigenesis via direct interactions with gastric epithelial cells in the TMPC-ANXA2-MAPK axis.
Topics: Animals; Humans; Mice; Atrophy; Carcinogenesis; Cell Transformation, Neoplastic; Gastric Mucosa; Gastritis; Inflammation; Mitogen-Activated Protein Kinases; Stomach Neoplasms; Streptococcus anginosus; Streptococcal Infections
PubMed: 38295787
DOI: 10.1016/j.cell.2024.01.004 -
Infection and Immunity Mar 2024Oral streptococci, key players in oral biofilm formation, are implicated in oral dysbiosis and various clinical conditions, including dental caries, gingivitis,...
Oral streptococci, key players in oral biofilm formation, are implicated in oral dysbiosis and various clinical conditions, including dental caries, gingivitis, periodontal disease, and oral cancer. Specifically, is associated with esophageal, gastric, and pharyngeal cancers, while is linked to oral cancer. However, no study has investigated the mechanistic links between these species and cancer-related inflammatory responses. As an initial step, we probed the innate immune response triggered by and in RAW264.7 macrophages. These bacteria exerted time- and dose-dependent effects on macrophage morphology without affecting cell viability. Compared with untreated macrophages, macrophages infected with exhibited a robust proinflammatory response characterized by significantly increased levels of inflammatory cytokines and mediators, including TNF, IL-6, IL-1β, NOS2, and COX2, accompanied by enhanced NF-κB activation. In contrast, -infected macrophages failed to elicit a robust inflammatory response. Seahorse Xfe96 analysis revealed an increased extracellular acidification rate in macrophages infected with compared with . At the 24-h time point, the presence of led to reduced extracellular itaconate, while triggered increased itaconate levels, highlighting distinct metabolic profiles in macrophages during infection in contrast to aconitate decarboxylase expression observed at the 6-h time point. This initial investigation highlights how and , two Gram-positive bacteria from the same genus, can prompt distinct immune responses and metabolic shifts in macrophages during infection.IMPORTANCEThe surge in head and neck cancer cases among individuals devoid of typical risk factors such as Human Papilloma Virus (HPV) infection and tobacco and alcohol use sparks an argumentative discussion around the emerging role of oral microbiota as a novel risk factor in oral squamous cell carcinoma (OSCC). While substantial research has dissected the gut microbiome's influence on physiology, the oral microbiome, notably oral streptococci, has been underappreciated during mucosal immunopathogenesis. , a viridans streptococci group, has been linked to abscess formation and an elevated presence in esophageal cancer and OSCC. The current study aims to probe the innate immune response to compared with the early colonizer as an important first step toward understanding the impact of distinct oral species on the host immune response, which is an understudied determinant of OSCC development and progression.
Topics: Humans; Streptococcus anginosus; Carcinoma, Squamous Cell; Mouth Neoplasms; Dental Caries; Streptococcus; Macrophages; Succinates
PubMed: 38289109
DOI: 10.1128/iai.00536-23 -
International Journal of Molecular... Jan 2024The effects of TiO nanotube (TNT) and reduced graphene oxide (rGO) deposition onto titanium, which is widely used in dental implants, on () and preosteoblastic cells...
The effects of TiO nanotube (TNT) and reduced graphene oxide (rGO) deposition onto titanium, which is widely used in dental implants, on () and preosteoblastic cells were evaluated. TNTs were formed through anodic oxidation on pure titanium, and rGO was deposited using an atmospheric plasma generator. The specimens used were divided into a control group of titanium specimens and three experimental groups: Group N (specimens with TNT formation), Group G (rGO-deposited specimens), and Group NG (specimens under rGO deposition after TNT formation). Adhesion of to the surface was assessed after 24 h of culture using a crystal violet assay, while adhesion and proliferation of MC3T3-E1 cells, a mouse preosteoblastic cell line, were evaluated after 24 and 72 h through a water-soluble tetrazolium salt assay. TNT formation and rGO deposition on titanium decreased adhesion ( < 0.05) and increased MC3T3-E1 cell adhesion and proliferation ( < 0.0083). In Group NG, adhesion was the lowest ( < 0.05), while MC3T3-E1 cell proliferation was the highest ( < 0.0083). In this study, TNT formation and rGO deposition on a pure titanium surface inhibited the adhesion of at an early stage and increased the initial adhesion and proliferation of preosteoblastic cells.
Topics: Mice; Animals; Streptococcus mutans; Titanium; Surface Properties; Nanotubes; Graphite
PubMed: 38279351
DOI: 10.3390/ijms25021351 -
Journal of Dentistry Mar 2024Secondary caries is a primary cause of early restoration failure. While primary dental caries has been extensively researched, our knowledge about the impact of...
OBJECTIVE
Secondary caries is a primary cause of early restoration failure. While primary dental caries has been extensively researched, our knowledge about the impact of secondary caries on dental restorations is relatively limited. In this study, we examined how different clinically relevant microbially-influenced environments impact the degradation of nano-filled (FIL) and micro-hybrid (AEL) dental composites.
METHODS
Material strength of two commercial dental composites was measured following incubation in aqueous media containing: i) cariogenic (Streptococcus mutans) and non-cariogenic bacteria (Streptococcus sanguinis) grown on sucrose or glucose, ii) abiotic mixtures of artificial saliva and sucrose and glucose fermentation products (volatile fatty acids and ethanol) in proportions known to be produced by these microorganisms, and iii) abiotic mixtures of artificial saliva and esterase, a common oral extracellular enzyme.
RESULTS
Nano-filled FIL composite strength decreased in all three types of incubations, while micro-hybrid AEL composite strength only decreased significantly in biotic incubations. The strength of both composites was statistically significantly decreased in all biotic incubations containing both cariogenic and non-cariogenic bacteria beyond that induced by either abiotic mixtures of fermentation products or esterase alone. Finally, there were no statistically significant differences in composite strength decrease among the tested biotic conditions.
CONCLUSIONS
The results show that conditions created during the growth of both cariogenic and non-cariogenic oral Streptococci substantially reduce commercial composite strength, and this effect warrants further study to identify the mechanism(s).
CLINICAL SIGNIFICANCE
Dental biofilms of oral Streptococci bacteria significantly affect the mechanical strength of dental restorations.
Topics: Humans; Dental Caries; Saliva, Artificial; Streptococcus; Streptococcus mutans; Dental Materials; Biofilms; Esterases; Sucrose; Glucose
PubMed: 38278316
DOI: 10.1016/j.jdent.2024.104861 -
Medicina (Kaunas, Lithuania) Dec 2023: This study evaluated the antimicrobial effect and cytotoxic potential of the natural extract against (), the causative agent of dental caries, which is a typical...
: This study evaluated the antimicrobial effect and cytotoxic potential of the natural extract against (), the causative agent of dental caries, which is a typical oral disease, and (), which causes oral candidiasis. : was shaken in 70% ethanol for 12 h to obtain samples through enrichment and lyophilization. Then, 1, 5, 10, 20, 30, and 40 mg/mL of the extract were applied to and to demonstrate its antimicrobial effect after 24 h. The stability of extract on the survival rate of human keratinocytes (HaCaT) was confirmed using water-soluble tetrazolium salt (WST-1) analysis. A one-way ANOVA determined the difference between each group. A Tukey HSD test was performed as a post-hoc analysis at the 0.05 significance level. : extract showed antimicrobial effects against and that increased in a concentration-dependent manner. However, high concentrations affected cell growth and lowered cell survival. The half maximal inhibitory concentration (IC value) of extract showed a survival rate of 53.04% at a concentration of 30 mg/mL, which was found to be applicable. : Thus, extract may be used as a natural material for the prevention and treatment of oral diseases. demonstrates optimal antimicrobial effects without affecting cell proliferation and growth at 30 mg/mL concentration.
Topics: Humans; Dental Caries; Plant Extracts; Streptococcus mutans; Candida albicans; Anti-Infective Agents; Biofilms
PubMed: 38276047
DOI: 10.3390/medicina60010013 -
Molecules (Basel, Switzerland) Jan 2024, the primary cause of dental caries, relies on its ability to create and sustain a biofilm (dental plaque) for survival and pathogenicity in the oral cavity. This study...
, the primary cause of dental caries, relies on its ability to create and sustain a biofilm (dental plaque) for survival and pathogenicity in the oral cavity. This study was focused on the antimicrobial biofilm formation control and biofilm dispersal potential of Coumaric acid (CA) against on the dentin surface. The biofilm was analyzed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) viability assay, microtiter plate assay, production of extracellular polymeric substances (EPSs), florescence microscopy (surface coverage and biomass μm) and three-dimensional (3D) surface plots. It was observed that CA at 0.01 mg/mL reduced bacterial growth by 5.51%, whereases at 1 mg/mL, a significant ( < 0.05) reduction (98.37%) was observed. However, at 1 mg/mL of CA, a 95.48% biofilm formation reduction was achieved, while a 73.45% biofilm dispersal (after 24 h. treatment) was achieved against the preformed biofilm. The MTT assay showed that at 1 mg/mL of CA, the viability of bacteria in the biofilm was markedly ( < 0.05) reduced to 73.44%. Moreover, polysaccharide (EPS) was reduced to 24.80 μg/mL and protein (EPS) to 41.47 μg/mL. ImageJ software (version 1.54 g) was used to process florescence images, and it was observed that the biofilm mass was reduced to 213 (μm); the surface coverage was reduced to 0.079%. Furthermore, the 3D surface plots showed that the untreated biofilm was highly dense, with more fibril-like projections. Additionally, molecular docking predicted a possible interaction pattern of CA (ligand) with the receptor Competence Stimulating Peptide (UA159sp, PDB ID: 2I2J). Our findings suggest that CA has antibacterial and biofilm control efficacy against associated with dental plaque under tested conditions.
Topics: Humans; Coumaric Acids; Dental Caries; Dental Plaque; Molecular Docking Simulation; Streptococcus mutans; Biofilms; Dentin
PubMed: 38257309
DOI: 10.3390/molecules29020397 -
International Journal of Molecular... Jan 2024Shikonin is extracted from the roots of , and shikonin extracts have been shown to have inhibitory effects on several bacteria. However, shikonin extracts are difficult...
Shikonin is extracted from the roots of , and shikonin extracts have been shown to have inhibitory effects on several bacteria. However, shikonin extracts are difficult to formulate because of their poor water solubility. In the present study, we prepared a shikonin dispersion, which was solubilized by the inclusion of β-1,3-1,6 glucan, and analysed the inhibitory effects of this dispersion on and non-mutans streptococci. The shikonin dispersion showed pronounced anti- activity, and inhibited growth of and biofilm formation by this bacterium. The shikonin dispersion also showed antimicrobial and antiproliferative effects against non-mutans streptococci. In addition, a clinical trial was conducted in which 20 subjects were asked to brush their teeth for 1 week using either shikonin dispersion-containing or non-containing toothpaste, respectively. The shikonin-containing toothpaste decreased the number of in the oral cavity, while no such effect was observed after the use of the shikonin-free toothpaste. These results suggest that shikonin dispersion has an inhibitory effect on and non-mutans streptococci, and toothpaste containing shikonin dispersion may be effective in preventing dental caries.
Topics: Humans; Lithospermum; Dental Caries; Streptococcus mutans; Toothpastes; Antibodies; Glucans; Plant Extracts; Naphthoquinones
PubMed: 38256148
DOI: 10.3390/ijms25021075