Oral Pathogens Research Articles

Green Synthesized Zinc Oxide Nanoparticles with Salvadora persica L. Root Extract and Their Antagonistic Activity Against Oral and Health-Threatening Pathogens

Green Synthesized Zinc Oxide Nanoparticles with Salvadora persica L. Root Extract and Their Antagonistic Activity Against Oral and Health-Threatening Pathogens

Higher Prevalence of the Periodontal Pathogen Selenomonas noxia among Pediatric and Adult Patients May Be Associated with Overweight and Obesity.

New evidence has suggested that oral and gut microflora may have significant impacts on the predisposition, development, and stability of obesity in adults over time-although less is known about this phenomenon in children. Compared with healthy-weight controls, overweight and obese adult patients are now known to harbor specific pathogens, such as Selenomonas noxia (S. noxia), that are capable of digesting normally non-digestible cellulose and fibers that significantly increase caloric extraction from normal dietary intake. To evaluate this phenomenon, clinical saliva samples (N = 122) from subjects with a normal BMI (18-25) and a BMI over 25 (overweight, obese) from an existing biorepository were screened using qPCR. The prevalence of S. noxia in samples from normal-BMI participants were lower (21.4%) than in overweight-BMI (25-29; 46.1%) and obese-BMI (30 and above; 36.8%) samples-a strong, positive correlation that was not significantly affected by age or race and ethnicity. These data strongly suggest that S. noxia may be intricately associated with overweight and obesity among patients, and more research will be needed to determine the positive and negative feedback mechanisms that may be responsible for these observations as well as the interventions needed to remove or reduce the potential effects of this oral pathogen.

Do Concurrent Peri-Implantitis and Periodontitis Share Their Microbiotas? A Pilot Study.

The microbial compositions from concurrent peri-implant and periodontal lesions were compared, since the results reported in the literature on the etiological relationship between these oral pathologies are contradictory. Microbial compositions from nine patients were evaluated using Illumina MiSeq sequencing of 16S rRNA gene amplicons and Principal Components Analysis. Comparisons between the use of curettes or paper points as collection methods and between bacterial composition in both pathologies were performed. Paper points allowed the recovery of a higher number of bacterial genera. A higher bacterial diversity was found in peri-implantitis compared to periodontal samples from the same patient, while a greater number of operational taxonomic units (OTUs) were present in the corresponding periodontal samples. A higher abundance of oral pathogens, such as Porphyromonas or Treponema, was found in peri-implantitis sites. The opposite trend was observed for Aggregatibacter abundance, which was higher in periodontal than in peri-implantitis lesions, suggesting that both oral pathologies could be considered different but related diseases. Although the analysis of a higher number of samples would be needed, the differences regarding the microbial composition provide a basis for further understating the pathogenesis of peri-implant infections.

Potential role of Citrus bergamia flower essential oil against oral pathogens

BackgroundOral bacterial infections are difficult to treat due to emergence of resistance against antibiotic therapy. Essential oils are considered emerging alternate therapy against bacterial infections and biofilms. We investigated Citrus bergemia flower essential oil against oral pathogens.MethodsThe essential oil was analsyed using Gas Chromatography(GC–MS), in silico investigations, antioxidant, antimicrobial, antibiofilm and antiquorum sensing assays.ResultsGas Chromatography analysis confirmed presence of 17 compounds including 1,6-Octadien-3-ol,3,7-dimethyl, 48.17%), l-limonene (22.03%) and p-menth-1-ol, 8-ol (7.31%) as major components. In silico analysis showed compliance of all tested major components with Lipinski’s rule, Bioavailability and antimicrobial activity using PASS (prediction of activity spectrum of substances). Molecular docking with transcriptional regulators 3QP5, 5OE3, 4B2O and 3Q3D revealed strong interaction of all tested compounds except 1,6-Octadien-3-ol,3,7-dimethyl. All tested compounds presented significant inhibition of DPPH (2,2-diphenyl-1-picrylhydrazyl) (IC50 0.65 mg/mL), H2O2 (hydrogen peroxide) (63.5%) and high FRAP (ferrous reducing antioxidant power) value (239.01 µg). In antimicrobial screening a significant activity (MIC 0.125 mg/mL) against Bacillus paramycoides and Bacillus chungangensis was observed. Likewise a strong antibiofilm (52.1 – 69.5%) and anti-QS (quorum sensing) (4–16 mm) activity was recorded in a dose dependent manner.ConclusionIt was therefore concluded that C. bergemia essential oil posess strong antioxidant, antimicrobial and antibiofilm activities against tested oral pathogens.

Preventive and Therapeutic Potential of Streptococcus cristatus CA119 in Experimental Periodontitis in Rats.

Periodontitis is an inflammatory condition of the oral cavity caused by a mixed infection of various bacteria, which not only severely affects the alveolar bone and connective tissues but also displays potential correlations with distal intestinal inflammation. In this study, we aimed to elucidate the therapeutic effects of Streptococcus cristatus CA119 on experimental periodontitis in rats and its impact on intestinal morphology. The results demonstrate that CA119 is capable of colonizing the oral cavity and exerting antagonistic effects on Porphyromonas gingivalis and Fusobacterium nucleatum, thus leading to a significant reduction in the oral pathogen load. Following CA119 intervention, there was a significant alleviation of weight loss in rats induced by periodontitis (P < 0.001). CA119 also regulated the expression of IL-6 (P < 0.05), IL-1β (P < 0.001), IL-18 (P < 0.001), COX-2 (P < 0.001), iNOS (P < 0.001), and MCP-1 (P < 0.01) in the gingival tissue. Additionally, CA119 reduced oxidative stress levels in rats and enhanced their antioxidant capacity. Microcomputed tomography (micro-CT) and histological analysis revealed that CA119 significantly reduced alveolar bone loss and reversed the downregulation of OPG/RANKL (P < 0.001). Furthermore, CA119 exhibited a significant protective effect against intestinal inflammation induced by periodontal disease and improved the colonic morphology in rats. In conclusion, this study demonstrates the role of CA119 as a potential oral probiotic in the prevention and treatment of experimental periodontitis, underscoring the potential of probiotics as a complementary approach to traditional periodontal care.

Chemical Composition and Antimicrobial Activity of Essential Oils and Hydrosols from Oregano, Sage and Pennyroyal against Oral Pathogens

In this study, the chemical composition of essential oils (EOs) extracted from Origanum vulgare ssp. hirtum Lamiaceae, (oregano), Salvia officinalis Lamiaceae (sage), Mentha pulegium Lamiaceae (pennyroyal), and respective hydrosols (HSs) has been investigated by Gas Chromatography–Mass Spectrometry (GC-MS). The antimicrobial activity was assessed against two oral pathogens: Gram-positive bacterium Streptococcus mutans and the fungus Candida albicans by determination of Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal/Fungicidal concentration (MBC/MFC). Three-fold diluted solutions were dispensed into each well of a 96-well microtiter plate and, after incubation, MIC was determined by visual monitoring. The MBC/MFC was determined by transferring a small quantity of sample contained in each replicate well of the microtiter plates to appropriate culture media using a microplate replicator. The EOs of the tested herbs showed antimicrobial properties, especially the EO oil of O. vulgare, which exerted the highest antimicrobial activity. HSs of S. officinalis and M. pulegium exerted no antimicrobial activity, in contrast to oregano HS, which displayed strong antimicrobial activity. In all cases, a higher number of compounds were detected in EOs than in the corresponding HSs. The major compounds of sage EO were detected to be α-thujone (25.1%), 1,8-cineole (15.8%) and β-pinene (10.0%), while the HS was characterized by the presence of 1,8-cineole (32.6%), borneol (22.6%) and α-thujone (22.4%). Pennyroyal EO and HS consists mainly of pulegone (62.1 and 50.6%, respectively). Carvacrol was the major component present in EO (63%) and HS (97.3%) of oregano, probably contributing to the antimicrobial activity. Further research is needed in order to elucidate the antimicrobial mechanisms of specific compounds present in essential oils and hydrosols of Lamiaceae grown in Greece against oral pathogens.

Antibacterial Herbal Mouthwash Formulation and Evaluation Against Oral Disorders

The goal of the present study is to create and assess a herbal mouthwash and determine how well it works to lower oral cavity bacterial counts. Following their collection, the plant materials' water-soluble components were removed. We also assessed the mouthwash's physicochemical characteristics and antibacterial efficacy. The mouthwash that is now available on the market has strong antimicrobial qualities. The stability investigation's findings attest to the preparation's efficacy. These days, mouthwash is marketed as a liquid and usually includes antiseptic and antibacterial ingredients. These solutions have the potential to serve several purposes, including inhibiting the growth of germs in the oral cavity and acting as an analgesic, anti-inflammatory, or anti-fungal agent. The oral cavity is home to a variety of microbes. While certain types of oral bacteria are harmless, others can lead to mouth illnesses, plaque buildup in the mouth, and bad breath. Therefore, keeping good oral hygiene is essential for both physical and mental well-being. The effectiveness of herbs is thought to be relatively high when compared to chemical products. Medicinal plants are crucial in treating a variety of illnesses due to their potent antibacterial and antifungal effects against human infections. Herbal remedies aid in tooth cleaning, reduce dental plaque, inhibit the growth of bacteria, and freshen breath. Herbal mouthwashes can be used in addition to your normal dental hygiene routine, which includes brushing and flossing. They are helpful in supportive periodontal treatment because of their potent antiinflammatory and anti-plaque characteristics. Many herbal remedies and their extracts, including those made from peppermint, cloves, neem, and turmeric, have demonstrated notable benefits over synthetic alternatives. Due to their long-lasting anti-bacterial, antimicrobial, and anti-fungal actions on human pathogens, medicinal herbs are essential for the treatment of illness. Using natural mouthwash in place of conventional ones may have several advantages. If a formulation like this could be invented that folks could safely and simply prepare at home using natural ingredients. As a result, the general oral health of the community could get better. Because they function on oral infections, quickly relieve pain, have few or no side effects, and target oral pathogens, herbal mouthwashes are quite popular. Among the most common infectious diseases that many individuals encounter at different times in their life are dental caries and periodontal disease. The purpose of this article is to give a general review of natural substances that can be effective mouthwashes. The objective of this study was to use polyherbal components to make mouthwash that has antibacterial properties.

Antioxidant, Anti-inflammatory, and Antimicrobial Activity of the Kalanchoe pinnata and Piper longum Formulation Against Oral Pathogens.

Background Dental caries stands out as a significant global infectious disease, with oral diseases posing substantial health concerns primarily due to bacterial, fungal, and yeast infections. Kalanchoe pinnata demonstrates antimicrobial, anticancer, antiparasitic, and hepatoprotective properties, with applications in various ailments. Piper longum exhibits potent antimicrobial effects against bacterial and viral pathogens due to the bioactive compounds within the plant. This study aims to assess the antimicrobial efficacy of P. longum and K. pinnata formulation against oral pathogens and evaluate its other biomedical potential. Methodology The agar well diffusion method was employed to assess the antimicrobial activity of the formulation containing P. longum and K. pinnata against oral pathogens. The protein leakage assay was employed to assess the ability of the prepared formulation to cause protein release from oral pathogens. The other biomedical potentials of the prepared formulation including cytotoxic effects, antioxidant, and anti-inflammatory properties were investigated using in vitro assays. Results The prepared P. longum and K. pinnata formulation demonstrated significant antimicrobial activity against tested oral pathogens, with inhibition zones observed for Staphylococcus aureus (32 mm), Streptococcus mutans (22 mm), and Candida albicans (12 mm). However, no inhibition was observed on Enterococcus faecalis at the highest concentration of 100 μL. Additionally, the formulation demonstrated significant antioxidant activity with percentages of 89.22%, 84.4%, and 86.93% in2,2-diphenyl-1-picrylhydrazyl (DPPH), hydrogen peroxide (H2O2), and ferric (Fe3+)-reducing antioxidant power assays, respectively, at the maximum concentration of 50 μL. Furthermore, the formulation exhibited potential anti-inflammatory activity, as evidenced by 79% inhibition in bovine serum albumin (BSA) denaturation assay and 77% inhibition in egg albumin (EA) denaturation assay at the highest concentration of 50 μL. Additionally, the formulation displayed low cytotoxic effects, even at the highest concentration of 80 μL. Conclusion K. pinnataandP. longumformulation demonstrated potential antimicrobial efficacy against oral pathogens and exhibited diverse therapeutic potentials. Thus, the developed formulation could be used as a potential alternative for pharmaceutical drugs against oral pathogens.

Safety and Beneficial Properties of Bacteriocinogenic Lactococcus lactis and Pediococcus pentosaceus Strains, and Their Effect Versus Oral Cavity Related and Antibiotic-Resistant Pathogens.

Pediococcus pentosaceus 732, Lactococcus lactis subsp. lactis 431, and Lactococcus lactis 808, bacteriocinogenic strains previously isolated from kimchi and banana, were investigated for their safety, beneficial properties and in vitro inhibition of pathogens such as Listeria monocytogenes ATCC 15313 and Staphylococcus simulans KACC 13241 and Staphylococcus auricularis KACC 13252. The results of performed physiological, biochemical, and biomolecular tests suggest that these strains can be deemed safe, as no virulence genes were detected in their DNA. Notably, only the gad gene associated with GABA production was identified in the DNA isolated of Lc. lactis 808 and Lc. lactis subsp. lactis 431 strains. All tested LAB strains exhibited γ-hemolysins and were non-producers of gelatinase and biogenic amines, which suggested their safety potential. Additionally, they were relatively susceptible to antibiotics except for streptomycin, tobramycin, and vancomycin for Pd. pentosaceus 732. The growth of Pd. pentosaceus 732, Lc. lactis subsp. lactis 431, and Lc. lactis 808 and their survival were minimally affected by up to 3% ox bile and low pH (except pH 2.0 and 4.0). Moreover, these LAB strains were not inhibited by various commercial extracts as well as most of the tested medications tested in the study. They did not produce proteolytic enzymes but exhibited production of D/L-lactic acid and β-galactosidase. They were also hydrophilic. Furthermore, their survival in artificial saliva, gastric simulation, and enteric passage was measured followed by a challenge test to assess their ability to inhibit the selected oral pathogens in an oral saliva model conditions.

Evaluation of Antimicrobial and Cytotoxic Activity of Nanoformulated Chamomile and Green Tea-Based Mouthwash: An In Vitro Study.

Introduction Nanotechnology plays a significant role in the biomedical and dental fields, offering numerous benefits to humans. Particularly, nanoparticles synthesised through green methods involving herbal formulations present promising advantages. Zinc oxide nanoparticles (ZnONPs)demonstrate strong antibacterial properties. Utilising treatments incorporating chamomile tea and green tea may potentially reduce toxicity while enhancing antibacterial effectiveness against oral infections. This study aimed to develop a mouthwash containing ZnONPs, followed by an evaluation of both its cytotoxicity and antibacterial effectiveness. Materials and methods This study was conducted at Saveetha Dental College, Saveetha Institute of Medical and Technical Science, Chennai, India. In the synthesis of ZnONPs, a formulation consisting of chamomile tea and green tea was employed. Subsequently, these synthesised nanoparticles were used in the preparation of mouthwash. An antimicrobial test of the produced ZnONPs was carried out using the agar well diffusion technique for oral pathogens. For analysis ofcytotoxicity, brine shrimps were used in an assay, and comparisons were made with a commercially available mouthwash. Results The antimicrobial properties were assessed, and the formulated mouthwash demonstrated a zone of inhibition of Staphylococcus aureus (20 mm), Enterococcus faecalis (11 mm), Streptococcus mutans (15 mm)and Candida albicans (13 mm), when the agar welldiffusion assay was carried out.Furthermore, the formulated mouthwash exhibited lower cytotoxicity compared to the commercially available mouthwash when cytotoxicity was checked in brine shrimps. Conclusion In our study, the ZnONPsynthesis with chamomile tea and green tea showed notable antibacterial and antifungal effects. In addition,lower toxicity was observed compared to the commercially available mouthwash. These findings suggest that mouthwash formulated with green-synthesis ZnONPs could serve as a viable alternative to synthetic mouthwash options. As a result, it is suggested that ZnONPs could be employed in mouthwash formulations at concentrations of 40 µL.

Unveiling the In Vitro Anti-Biofilm Potential of Lactobacillus rhamnosus Against Saliva-Based Pathogens: A Gender-Age-Area Specific Study

ABSTRACT Probiotics, like lactobacilli and bifidobacteria, benefit health by populating the digestive system, which houses numerous microbial species. Studies demonstrate their ability to inhibit biofilm formation, crucial in preventing oral conditions like dental caries. Our research evaluated a probiotic strain’s anti-biofilm efficacy against oral pathogens in 45 individuals’ saliva, alongside its biofilm-forming potential. Analysis revealed significant biofilm inhibition in 36 samples. Comparisons based on age, gender, and geography further supported these findings. We propose further exploration of probiotics tailored to specific demographics to enhance oral health outcomes, suggesting a promising avenue for preventing oral microbial diseases.

Evaluation of Jati (Jasminum grandiflorum L.) mouthwash and Jati Kwatha (decoction) in Mukhapaka (aphthous stomatitis): An open-label, randomized, placebo-controlled clinical study

Abstract Background: Leaf extract of Jati (Jasminum grandiflorum L.) has been proven to possess dermal wound healing and anti-ulcer activities. Mukhapaka (aphthous stomatitis) is the most common lesion of the oral cavity. For its management, Jati mouthwash was formulated by the Arka (distillation), and its efficacy was compared with the traditional form of Jati Kwatha (decoction). Due consideration was given to patient compliance, convenience of usage, increased shelf-life, no preservative, easy storage, and dispensing. Aims: The aim of this study was to evaluate the efficacy of Jati mouthwash and Jati Kwatha Kavala (gargle) in the management of Mukhapaka. ] Materials and methods: Forty-five patients having the classical symptoms of Mukhapaka were randomized into three groups as Jati mouthwash (group 1), Jati Kwatha Kavala (group II), and placebo (group III), all preparations were administered twice daily for seven days. The assessment was done by scoring method evaluating the oral ulcer activity, ulcer-related pain and functional disability, and Visual Analog Scale (VAS) at the baseline each day. Statistical evaluation was done within groups using paired t-test and between the groups using ANOVA post hoc multiple comparisons – Tukeys test. Results: Significant reductions was observed in VAS score for pain and other symptoms in the Jati mouthwash group at the end of seven days. Furthermore, the mouthwash group noted an accelerated mean healing period. Gas chromatography–mass spectrometry spectrum of the drug in its modified form as distillate revealed the presence of thymol and carvacrol, which are proven effective against oral pathogens but were absent in the Kwatha. Conclusion: Although the disease is self-limiting and the management is supportive, the Jati mouthwash was found to be better than its classical form of Kwatha or decoction.

Selective production of two prebiotic extracellular polysaccharides from an oral probiotic lactic acid bacterium, Streptococcus salivarius SY511

Streptococcus salivarius is a lactic acid bacterium and an oral probiotic species. Growth of S. salivarius in a sucrose medium can lead to the production of exopolysaccharides (EPSs) that are potential prebiotics. However, no studies have yet examined use of this species for the selective production of high concentrations of EPSs. In this study, we isolated S. salivarius SY511 from infant feces and grew it in a sucrose medium to produce high levels of water-insoluble and water-soluble EPSs. NMR and monosaccharide analysis demonstrated that water-insoluble glucan and water-soluble levan were the two main EPSs. Batch fermentation in MRS-sucrose medium led to the efficient production of these two EPSs, and Tween 80 was a key factor that affected their differential production. In the fed-batch fermentation, 22.7 g/L of water-insoluble glucan was produced in the MRS-sucrose medium, while 24.9 g/L of levan was produced in the MRS-sucrose medium without Tween 80. Compared to S. salivarius M18, S. salivarius SY511 had higher or similar antimicrobial activity against major oral pathogens. Furthermore, the water-insoluble glucan and levan from S. salivarius SY511 had excellent prebiotic, anti-inflammatory, and antioxidant effects. Our study of S. salivarius SY511 identified a method for the selective production of two EPSs.

A Comparative Evaluation of Antimicrobial and Cytotoxic Efficacy of Biosynthesized Silver Nanoparticles and Chemically Synthesized Silver Nanoparticles Against Enterococcus faecalis: An In Vitro Study.

Introduction Effective root canal cleaning and sealing are essential for a successful endodontic procedure. For the purpose of disinfecting root canals, both herbal and non-herbal medications are recommended. This study aimed to analyze the antimicrobialand cytotoxic properties of biosynthesized silver nanoparticles (AgNPs)synthesized from Azadirachta indica/neem and chemically synthesized AgNPs from trisodium citrate (TSC) against oral pathogens to be further used as an irrigant in endodontic treatment. Materials and methods To synthesizeA. indicaAgNPs, powdered fresh A. indicaleaves were weighed, added to double distilled water, heated for 30 minutes, and then combined with silver nitrate solution. TSC was also used to create TSC AgNPs. X-ray diffraction (XRD), scanning electron microscopy (SEM), ocular observation, and the ultraviolet-visible light (UV-vis) spectrum were used to characterize the AgNPs. Studies were conducted on the extract's characteristics, including its cytotoxicity and antibacterial activity. Results The hue shift and peak on the UV-vis spectrophotometer were signs that AgNPs were forming. The XRD pattern showed that the sample included crystalline AgNPs, mostly spherical ones. By using SEM, the presence of AgNPs was also verified. AgNPs that were synthesized showed antimicrobial efficacy against Enterococcusfaecalis. Compared to chemically synthesized AgNPs, A. indica AgNPs showedlower minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values, a bigger zone of inhibition (ZOI), and less cytotoxic action. Conclusion This study demonstrates the minimal cytotoxicity and antibacterial activity of A. indica AgNPs against E. faecalis. This suggests that they might also be employed asroot canal cleaners. Before experimenting with animals or cell lines in clinical trials for endodontic treatment, further research should be done.

Frankincense (Boswellia serrata) Extract Effects on Growth and Biofilm Formation of Porphyromonas gingivalis, and Its Intracellular Infection in Human Gingival Epithelial Cells.

Frankincense is produced by Boswellia trees, which can be found throughout the Middle East and parts of Africa and Asia. Boswellia serrata extract has been shown to have anti-cancer, anti-inflammatory, and antimicrobial effects. Periodontitis is an oral chronic inflammatory disease that affects nearly half of the US population. We investigated the antimicrobial effects of B. serrata extract on two oral pathogens associated with periodontitis. Using the minimum inhibitory concentration and crystal violet staining methods, we demonstrated that Porphyromonas gingivalis growth and biofilm formation were impaired by treatment with B. serrata extracts. However, the effects on Fusobacterium nucleatum growth and biofilm formation were not significant. Using quantification of colony-forming units and microscopy techniques, we also showed that concentrations of B. serrata that were not toxic for host cells decreased intracellular P. gingivalis infection in human gingival epithelial cells. Our results show antimicrobial activity of a natural product extracted from Boswellia trees (B. serrata) against periodontopathogens. Thus, B. serrata has the potential for preventing and/or treating periodontal diseases. Future studies will identify the molecular components of B. serrata extracts responsible for the beneficial effects.

Association of Filifactor alocis and its RTX toxin gene ftxA with periodontal attachment loss, and in synergy with Aggregatibacter actinomycetemcomitans.

The Gram-positive bacterium, Filifactor alocis is an oral pathogen, and approximately 50% of known strains encode a recently identified repeat-in-toxin (RTX) protein, FtxA. By assessing a longitudinal Ghanaian study population of adolescents (10-19 years of age; mean age 13.2 years), we recently discovered a possible correlation between deep periodontal pockets measured at the two-year follow-up, presence of the ftxA gene, and a high quantity of F. alocis. To further understand the contribution of F. alocis and FtxA in periodontal disease, we used qPCR in the present study to assess the carriage loads of F. alocis and the prevalence of its ftxA gene in subgingival plaque specimens, sampled at baseline from the Ghanaian cohort (n=500). Comparing these results with the recorded clinical attachment loss (CAL) longitudinal progression data from the two-year follow up, we concluded that carriers of ftxA-positive F. alocis typically exhibited higher loads of the bacterium. Moreover, high carriage loads of F. alocis and concomitant presence of the ftxA gene were two factors that were both associated with an enhanced prevalence of CAL progression. Interestingly, CAL progression appeared to be further promoted upon the simultaneous presence of F. alocis and the non-JP2 genotype of Aggregatibacter actinomycetemcomitans. Taken together, our present findings are consistent with the notion that F. alocis and its ftxA gene promotes CAL during periodontal disease.

Placental TLR recognition of salivary and subgingival microbiota is associated with pregnancy complications

BackgroundPre-term birth, the leading cause of neonatal mortality, has been associated with maternal periodontal disease and the presence of oral pathogens in the placenta. However, the mechanisms that underpin this link are not known. This investigation aimed to identify the origins of placental microbiota and to interrogate the association between parturition complications and immune recognition of placental microbial motifs.61FbVQciH1C2BbwKYgvy28Video MethodsSaliva, plaque, serum, and placenta were collected during 130 full-term (FT), pre-term (PT), or pre-term complicated by pre-eclampsia (PTPE) deliveries and subjected to whole-genome shotgun sequencing. Real-time quantitative PCR was used to measure toll-like receptors (TLR) 1–10 expression in placental samples. Source tracking was employed to trace the origins of the placental microbiota.ResultsWe discovered 10,007 functionally annotated genes representing 420 taxa in the placenta that could not be attributed to contamination. Placental microbial composition was the biggest discriminator of pregnancy complications, outweighing hypertension, BMI, smoking, and maternal age. A machine-learning algorithm trained on this microbial dataset predicted PTPE and PT with error rates of 4.05% and 8.6% (taxonomy) and 6.21% and 7.38% (function). Logistic regression revealed 32% higher odds of parturition complication (95% CI 2.8%, 81%) for every IQR increase in the Shannon diversity index after adjusting for maternal smoking status, maternal age, and gravida. We also discovered distinct expression patterns of TLRs that detect RNA- and DNA-containing antigens in the three groups, with significant upregulation of TLR9, and concomitant downregulation of TLR7 in PTPE and PT groups, and dense correlation networks between microbial genes and these TLRs. 70–82% of placental microbiota were traced to serum and thence to the salivary and subgingival microbiomes. The oral and serum microbiomes of PTPE and PT groups displayed significant enrichment of genes encoding iron transport, exosome, adhesion, quorum sensing, lipopolysaccharide, biofilm, and steroid degradation.ConclusionsWithin the limits of cross-sectional analysis, we find evidence to suggest that oral bacteria might translocate to the placenta via serum and trigger immune signaling pathways capable of inducing placental vascular pathology. This might explain, in part, the higher incidence of obstetric syndromes in women with periodontal disease.

Molecular dentistry: Polymerase chain reaction’s transformative role

Molecular dentistry, propelled by advancements in techniques such as Polymerase Chain Reaction (PCR), has emerged as a promising frontier in dental research and practice. PCR has revolutionized the field of dentistry by enabling precise and sensitive detection of various oral pathogens, genetic markers associated with dental diseases, and host response factors. Its ability to amplify specific DNA sequences from minimal starting material has facilitated rapid and accurate diagnosis of dental infections, periodontal diseases, and genetic predispositions to oral conditions. Moreover, PCR-based methods have enhanced our understanding of the oral microbiome composition and its relationship with overall health. This review article aims to elucidate the transformative role of PCR in molecular dentistry by providing an overview of its applications, current developments, and future prospects.

Copper-based nanodots as efficient biomimetic antibiotics for the treatment of oral bacterial infections

Oral infectious diseases caused by a variety of pathogenic bacteria seriously affect the quality of life. However, these diseases remain a clinical challenge because of the lack of simple, safe, and universal prophylactics. To address these limitations, we synthesize CuOx nanodots (CuOx NDs) with excellent Fenton-like reaction activity and utilize them in the treatment of oral bacterial infections. Different from other complicated approaches, CuOx NDs are rationally prepared using a facile one-pot aqueous synthesis. In the presence of H2O2, these well-developed CuOx NDs can efficiently catalyze the generation of hydroxyl radicals (·OH) around oral pathogens, leading to the death of various bacteria. Meanwhile, results of biosafety indicate the high biocompatibility and extremely low toxicity of these CuOx NDs. After understanding the admirable in vitro antibacterial effect of CuOx NDs in the presence of H2O2, we further explore their in vivo antibacterial performance on several classical animal models including oral mucosal wound model, intragingival bacteria-infected model, and the periodontal infection model. As expected, these CuOx NDs with wide-spectrum antibacterial activity can serve as high-performance antibacterial reagents for the treatment of various oral bacterial infections with the help of H2O2. In brief, current nanoplatform can act as efficient antibiotics against oral pathogens with broadening the biomedical applications of copper-based nanomaterials.

Abstract 6696: Microbial signatures and serum markers in colon cancer of African American patients

Abstract Among all the racial/ethnic groups, African American (AA) patients have the highest incidence of CRC and mortality rate. There is growing evidence indicating that the oral bacteria might translocate to the intestine, potentially causing disruptions in the balance of gut microbes. Our study delves into the complex interplay between oral pathogens, gut microbiota, and colon carcinogenesis in AA patients. Methods: 16S rRNA sequencing of tumor and non-tumor tissues, utilized qPCR for detection of oral bacteria Fusobacterium nucleatum (Fn) and Porphyromonas gingivalis (Pg) relative abundance, performed cytokine profiling via multiplex ELISA, and employed NAPPA for antibody response assessment. Results: Colon tumor tissues had lower microbial diversity, notably in right-sided tumors, with distinct biofilm-associated bacteria. Novel discoveries emerged from differential abundance testing, revealing Prevotella intermedia and Treponema socranski to be associated with early cancer stage and left-sided location, and Fusobacterium necrophorum with advanced cancer stage and right-sided location. qPCR demonstrated Fn and Pg elevation in right-sided tumors and late cancer stages. Both were detected in 45% of tumors versus 37% in non-tumor tissues and 19.15% of tumors and 25.53% in non-tumor tissues, respectively. Fn-positive groups exhibited distinct microbial signatures, with altered bacterial abundances and dysbiosis, including increased CRC-associated bacteria Faecalibacterium and Helicobacter, increased oral pathogen abundance (Fusobacterium, Porphyromonas, Prevotella, Treponema), and reduced beneficial bacteria. Serological analysis highlighted elevated levels of IL-2, IL-10, IFN-γ, and RANK in advanced cancer stages and increased CRP levels in right-sided tumors. By NAPPA analysis, 30 bacterial proteins (anti-IgG) showed a seroprevalence of more than 15% in the samples, with those being the most seroprevalent anti-HP131 and anti-HP-1564 (68% and 61% of all samples) of Helicobacter pylori, and anti-msnK (64%) of Streptococcus gallolyticus. Conclusions: Our study emphasized the reduced diversity in tumor tissues, particularly in right-sided tumors in AA colon cancer. Fn presence in colonic tumors correlated with CRC-associated bacteria and oral pathogen aggregation, suggesting its potential role in cancer pathogenesis. Combining the analysis of cytokines and pathogenic bacteria antibodies may serve as broader serological biomarkers for disease severity and location. These findings advance our comprehension of microbiota-cancer interactions, directing personalized diagnostics and treatments in this population. Citation Format: Sofia Carolina Tortora, Emily Vogtmann, Laura Martello-Rooney. Microbial signatures and serum markers in colon cancer of African American patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6696.