Piezo2,a mechanosensitive ion channel,serves as a crucial mechanotransducer in dental primary afferent(DPA)neurons and is potentially involved in hypersensitivity to mild mechanical irritations observed in dental pati...Piezo2,a mechanosensitive ion channel,serves as a crucial mechanotransducer in dental primary afferent(DPA)neurons and is potentially involved in hypersensitivity to mild mechanical irritations observed in dental patients.Given Piezo2’s widespread expression across diverse subpopulations of DPA neurons,this study aimed to characterize the mechanosensory properties of Piezo2-expressing DPA neurons with a focus on distinct features of voltage-gated sodium channels(VGSCs)and neuropeptide profiles.Using whole-cell patch-clamp recordings,we observed mechanically activated action potentials(APs)and classified AP waveforms based on the presence or absence of a hump during the repolarization phase.Single-cell reverse transcription polymerase chain reaction combined with patch-clamp recordings revealed specific associations between AP waveforms and molecular properties,including tetrodotoxin-resistant VGSCs(NaV1.8 and NaV1.9)and TRPV1 expression.Reanalysis of the transcriptomic dataset of DPA neurons identified correlations between neuropeptides—including two CGRP isoforms(α-CGRP andβ-CGRP),Substance P,and Galanin—and the expression of NaV1.8 and NaV1.9,which were linked to defined AP subtypes.These molecular associations were further validated in Piezo2+DPA neurons using fluorescence in situ hybridization.Together,these findings highlight the electrophysiological and neurochemical heterogeneity of Piezo2-expressing DPA neurons and their specialized roles in distinct mechanosensory signal transmission.展开更多
Understanding microbial-host interactions in the oral cavity is essential for elucidating oral disease pathogenesis and its systemic implications.In vitro bacteria-host cell coculture models have enabled fundamental s...Understanding microbial-host interactions in the oral cavity is essential for elucidating oral disease pathogenesis and its systemic implications.In vitro bacteria-host cell coculture models have enabled fundamental studies to characterize bacterial infection and host responses in a reductionist yet reproducible manner.However,existing in vitro coculture models fail to establish conditions that are suitable for the growth of both mammalian cells and anaerobes,thereby hindering a comprehensive understanding of their interactions.Here,we present an asymmetric gas coculture system that simulates the oral microenvironment by maintaining distinct normoxic and anaerobic conditions for gingival epithelial cells and anaerobic bacteria,respectively.Using a key oral pathobiont,Fusobacterium nucleatum,as the primary test bed,we demonstrate that the system preserves bacterial viability and supports the integrity of telomerase-immortalized gingival keratinocytes.Compared to conventional models,this system enhanced bacterial invasion,elevated intracellular bacterial loads,and elicited more robust host pro-inflammatory responses,including increased secretion of CXCL10,IL-6,and IL-8.In addition,the model enabled precise evaluation of antibiotic efficacy against intracellular pathogens.Finally,we validate the ability of the asymmetric system to support the proliferation of a more oxygen-sensitive oral pathobiont,Porphyromonas gingivalis.These results underscore the utility of this coculture platform for studying oral microbial pathogenesis and screening therapeutics,offering a physiologically relevant approach to advance oral and systemic health research.展开更多
Dentoalveolar bacterial infections cause localized tissue and bone destruction, but usually remain well-localized within teeth in immunocompetent hosts. However, in certain cases these infections may invade head and n...Dentoalveolar bacterial infections cause localized tissue and bone destruction, but usually remain well-localized within teeth in immunocompetent hosts. However, in certain cases these infections may invade head and neck tissues, resulting in orofacial abscesses, cellulitis and sepsis, with resultant high morbidity and even mortality. In the present studies, we developed a novel model of spreading dentoalveolar infections in mice by treatment with neutralizing antibodies against both interleukin-la （IL-1a） and IL-1β. Surprisingly male but not female mice given anti-lL-1 antibodies developed orofacial abscesses, weight loss, splenomegaly and sepsis. Female mice developed abscesses and sepsis comparable to males following ovariectomy （OVX）, which was reversed by estrogen supplementation. Anti-lL-1 blockade inhibited IL-12, interferon y （IFNy） and IL-6 but not IL-IO expression in infrabony lesions, suggestive of a local anti-inflammatory response. There was greater infiltration of neutrophils and other inflammatory ceils into lesions in anti-lL-l-treated animals; however, blood leukocytes had reduced bacterial phagocytic and killing activity ex vivo. Estrogen directly stimulated IL-1 production by macrophages, suggesting that the resistance of females to disseminating dentoalveolar infections may be due to their heightened pro-inflammatory responses following bacterial challenge, leading to enhanced localization of these infections.展开更多
Hypoxia（low oxygen level） is an important feature during infections and affects the host defence mechanisms. The host has evolved specific responses to address hypoxia, which are strongly dependent on the activation...Hypoxia（low oxygen level） is an important feature during infections and affects the host defence mechanisms. The host has evolved specific responses to address hypoxia, which are strongly dependent on the activation of hypoxia-inducible factor 1（HIF-1）.Hypoxia interferes degradation of HIF-1 alpha subunit（HIF-1α）, leading to stabilisation of HIF-1α, heterodimerization with HIF-1 beta subunit（HIF-1β） and subsequent activation of HIF-1 pathway. Apical periodontitis（periapical lesion） is a consequence of endodontic infection and ultimately results in destruction of tooth-supporting tissue, including alveolar bone. Thus far, the role of HIF-1 in periapical lesions has not been systematically examined. In the present study, we determined the role of HIF-1 in a wellcharacterised mouse periapical lesion model using two HIF-1α-activating strategies, dimethyloxalylglycine（DMOG） and adenovirusinduced constitutively active HIF-1α（CA-HIF1 A）. Both DMOG and CA-HIF1 A attenuated periapical inflammation and tissue destruction. The attenuation in vivo was associated with downregulation of nuclear factor-κappa B（NF-κB） and osteoclastic gene expressions. These two agents also suppressed NF-κB activation and subsequent production of proinflammatory cytokines by macrophages. Furthermore, activation of HIF-1α by DMOG specifically suppressed lipopolysaccharide-stimulated macrophage differentiation into M1 cells, increasing the ratio of M2 macrophages against M1 cells. Taken together, our data indicated that activation of HIF-1 plays a protective role in the development of apical periodontitis via downregulation of NF-κB, proinflammatory cytokines, M1 macrophages and osteoclastogenesis.展开更多
AIM:To design and validate broad-range 16S rRNA primers for use in high throughput sequencing to classify bacteria isolated from the human foregut microbiome.METHODS:A foregut microbiome dataset was constructed using ...AIM:To design and validate broad-range 16S rRNA primers for use in high throughput sequencing to classify bacteria isolated from the human foregut microbiome.METHODS:A foregut microbiome dataset was constructed using 16S rRNA gene sequences obtained from oral,esophageal,and gastric microbiomes produced by Sanger sequencing in previous studies represented by 219 bacterial species.Candidate primers evaluated were from the European rRNA database.To assess the effect of sequence length on accuracy of classification,16S rRNA genes of various lengths were created by trimming the full length sequences.Sequences spanning various hypervariable regions were selected to simulate the amplicons that would be obtained using possible primer pairs.The sequences were compared with full length 16S rRNA genes for accuracy in taxonomic classification using online software at the Ribosomal Database Project (RDP).The universality of the primer set was evaluated using the RDP 16S rRNA database which is comprised of 433 306 16S rRNA genes,represented by 36 phyla.RESULTS:Truncation to 100 nucleotides(nt)downstream from the position corresponding to base 28 in the Escherichia coli 16S rRNA gene caused misclassification of 87(39.7%)of the 219 sequences,compared with misclassification of only 29(13.2%)sequences with truncation to 350 nt.Among 350-nt sequence reads within various regions of the 16S rRNA gene,the reverse read of an amplicon generated using the 343F/798R primers had the least(8.2%)effect on classification.In comparison,truncation to 900 nt mimicking single pass Sanger reads misclassified 5.0%of the 219 sequences.The 343F/798R amplicon accurately assigned 91.8%of the 219 sequences at the species level.Weighted by abundance of the species in the esophageal dataset,the 343F/798R amplicon yielded similar classification accuracy without a significant loss in species coverage(92%).Modification of the 343F/798R primers to 347F/803R increased their universality among foregut species.Assuming that a typicalpolymerase chain reaction can tolerate 2 mismatches between a primer and a template,the modified 347F and 803R primers should be able to anneal 98%and 99.6%of all 16S rRNA genes in the RDP database.CONCLUSION:347F/803R is the most suitable pair of primers for classification of foregut 16S rRNA genes but also possess universality suitable for analyses of other complex microbiomes.展开更多
The role of third molars in the oral cavity has been extensively studied over the years. Literature includes numerous diagnostic and treatment alternatives regarding the third molars. However, an issue that has not be...The role of third molars in the oral cavity has been extensively studied over the years. Literature includes numerous diagnostic and treatment alternatives regarding the third molars. However, an issue that has not been discussed at the same level is their involvement in orthodontic therapy. The aim of this study is to present a review of the contemporary literature regarding the most broadly discussed aspects of the multifactorial role of third molars in orthodontics and which are of general dental interest too.展开更多
The biodiversity of the mycobiome,an important component of the oral microbial community,and the roles of fungal–bacterial and fungal–immune system interactions in the pathogenesis of oral lichen planus (OLP) remain...The biodiversity of the mycobiome,an important component of the oral microbial community,and the roles of fungal–bacterial and fungal–immune system interactions in the pathogenesis of oral lichen planus (OLP) remain largely uncharacterized.In this study,we sequenced the salivary mycobiome and bacteriome associated with OLP.First,we described the dysbiosis of the microbiome in OLP patients,which exhibits lower levels of fungi and higher levels of bacteria.Significantly higher abundances of the fungi Candida and Aspergillus in patients with reticular OLP and of Alternaria and Sclerotiniaceae_unidentified in patients with erosive OLP were observed compared to the healthy controls.Aspergillus was identified as an “OLP-associated” fungus because of its detection at a higher frequency than in the healthy controls.Second,the co-occurrence patterns of the salivary mycobiome–bacteriome demonstrated negative associations between specific fungal and bacterial taxa identified in the healthy controls,which diminished in the reticular OLP group and even became positive in the erosive OLP group.Moreover,the oral cavities of OLP patients were colonized by dysbiotic oral flora with lower ecological network complexity and decreased fungal–Firmicutes and increased fungal–Bacteroidetes sub-networks.Third,several keystone fungal genera (Bovista,Erysiphe,Psathyrella,etc.) demonstrated significant correlations with clinical scores and IL-17 levels.Thus,we established that fungal dysbiosis is associated with the aggravation of OLP.Fungal dysbiosis could alter the salivary bacteriome or may reflect a direct effect of host immunity,which participates in OLP pathogenesis.展开更多
Abstract:Ulcerative Colitis(UC)has been reported to be related to Porphyromonas gingivalis(P.gingivalis).Porphyromonas gingivalis peptidylarginine deiminase(PPAD),a virulence factor released by P.gingivalis,is known t...Abstract:Ulcerative Colitis(UC)has been reported to be related to Porphyromonas gingivalis(P.gingivalis).Porphyromonas gingivalis peptidylarginine deiminase(PPAD),a virulence factor released by P.gingivalis,is known to induce inflammatory responses.To explore the pathological relationships between PPAD and UC,we used homologous recombination technology to construct a P.gingivalis strain in which the PPAD gene was deleted(Δppad)and aΔppad strain in which the PPAD gene was restored(comΔppad).C57 BL/6 mice were orally gavaged with saline,P.gingivalis,Δppad,or comΔppad twice a week for the entire 40 days(days 0-40),and then,UC was induced by dextran sodium sulfate(DSS)solution for 10 days(days 31-40).P.gingivalis and comΔppad exacerbated DDS-induced colitis,which was determined by assessing the parameters of colon length,disease activity index,and histological activity index,butΔppad failed to exacerbate DDS-induced colitis.Flow cytometry and ELISA revealed that compared withΔppad,P.gingivalis,and comΔppad increased T helper 17(Th17)cell numbers and interleukin(IL)-17 production but decreased regulatory T cells(Tregs)numbers and IL-10 production in the spleens of mice with UC.We also cocultured P.gingivalis,Δppad,or comΔppad with T lymphocytes in vitro and found that P.gingivalis and comΔppad significantly increased Th17 cell numbers and decreased Treg cell numbers.Immunofluorescence staining of colon tissue paraffin sections also confirmed these results.The results suggested that P.gingivalis exacerbated the severity of UC in part via PPAD.展开更多
Oral squamous cell carcinoma(OSCC) is the most prevalent and most commonly studied oral cancer. However, there is a void regarding the role that the oral microbiome may play in OSCC. Although the relationship between ...Oral squamous cell carcinoma(OSCC) is the most prevalent and most commonly studied oral cancer. However, there is a void regarding the role that the oral microbiome may play in OSCC. Although the relationship between microbial community composition and OSCC has been thoroughly investigated, microbial profiles of the human microbiome in cancer are understudied. Here we performed a small pilot study of community-wide metatranscriptome analysis to profile mRNA expression in the entire oral microbiome in OSCC to reveal molecular functions associated with this disease. Fusobacteria showed a statistically significantly higher number of transcripts at tumour sites and tumour-adjacent sites of cancer patients compared to the healthy controls analysed. Regardless of the community composition, specific metabolic signatures were consistently found in disease. Activities such as iron ion transport, tryptophanase activity, peptidase activities and superoxide dismutase were over-represented in tumour and tumour-adjacent samples when compared to the healthy controls. The expression of putative virulence factors in the oral communities associated with OSCC showed that activities related to capsule biosynthesis, flagellum synthesis and assembly, chemotaxis, iron transport, haemolysins and adhesins were upregulated at tumour sites. Moreover, activities associated with protection against reactive nitrogen intermediates, chemotaxis, flagellar and capsule biosynthesis were also upregulated in non-tumour sites of cancer patients. Although they are preliminary, our results further suggest that Fusobacteria may be the leading phylogenetic group responsible for the increase in expression of virulence factors in the oral microbiome of OSCC patients.展开更多
基金supported by the National Research Foundation(NRF)of Korea(grant number:RS-2022-NR072217 to P.RL,RS-2021-NR059709,RS-2023-00264409,and RS-2024-00441103)funded by the Korean government(MSIT).
文摘Piezo2,a mechanosensitive ion channel,serves as a crucial mechanotransducer in dental primary afferent(DPA)neurons and is potentially involved in hypersensitivity to mild mechanical irritations observed in dental patients.Given Piezo2’s widespread expression across diverse subpopulations of DPA neurons,this study aimed to characterize the mechanosensory properties of Piezo2-expressing DPA neurons with a focus on distinct features of voltage-gated sodium channels(VGSCs)and neuropeptide profiles.Using whole-cell patch-clamp recordings,we observed mechanically activated action potentials(APs)and classified AP waveforms based on the presence or absence of a hump during the repolarization phase.Single-cell reverse transcription polymerase chain reaction combined with patch-clamp recordings revealed specific associations between AP waveforms and molecular properties,including tetrodotoxin-resistant VGSCs(NaV1.8 and NaV1.9)and TRPV1 expression.Reanalysis of the transcriptomic dataset of DPA neurons identified correlations between neuropeptides—including two CGRP isoforms(α-CGRP andβ-CGRP),Substance P,and Galanin—and the expression of NaV1.8 and NaV1.9,which were linked to defined AP subtypes.These molecular associations were further validated in Piezo2+DPA neurons using fluorescence in situ hybridization.Together,these findings highlight the electrophysiological and neurochemical heterogeneity of Piezo2-expressing DPA neurons and their specialized roles in distinct mechanosensory signal transmission.
基金supported by National Science Foundation CAREER (2238972)National Institute of Dental and Craniofacial Research awards (R03DE031329 and R01DE030943)The Translational Tissue Modeling Laboratory is supported by the University of Michigan (Center for Gastrointestinal Research,Office of the Dean, Comprehensive Cancer Center, and the Departments of Pathology, Pharmacology, and Internal Medicine) with additional funding from the Endowment for Basic Sciences
文摘Understanding microbial-host interactions in the oral cavity is essential for elucidating oral disease pathogenesis and its systemic implications.In vitro bacteria-host cell coculture models have enabled fundamental studies to characterize bacterial infection and host responses in a reductionist yet reproducible manner.However,existing in vitro coculture models fail to establish conditions that are suitable for the growth of both mammalian cells and anaerobes,thereby hindering a comprehensive understanding of their interactions.Here,we present an asymmetric gas coculture system that simulates the oral microenvironment by maintaining distinct normoxic and anaerobic conditions for gingival epithelial cells and anaerobic bacteria,respectively.Using a key oral pathobiont,Fusobacterium nucleatum,as the primary test bed,we demonstrate that the system preserves bacterial viability and supports the integrity of telomerase-immortalized gingival keratinocytes.Compared to conventional models,this system enhanced bacterial invasion,elevated intracellular bacterial loads,and elicited more robust host pro-inflammatory responses,including increased secretion of CXCL10,IL-6,and IL-8.In addition,the model enabled precise evaluation of antibiotic efficacy against intracellular pathogens.Finally,we validate the ability of the asymmetric system to support the proliferation of a more oxygen-sensitive oral pathobiont,Porphyromonas gingivalis.These results underscore the utility of this coculture platform for studying oral microbial pathogenesis and screening therapeutics,offering a physiologically relevant approach to advance oral and systemic health research.
基金supported by grant DE-11664(PS)from the National Institute of Dental and Craniofacial Research/National Institutes of Health(NIDCR/NIH)a grant from the American Association of Endodontists(HY)
文摘Dentoalveolar bacterial infections cause localized tissue and bone destruction, but usually remain well-localized within teeth in immunocompetent hosts. However, in certain cases these infections may invade head and neck tissues, resulting in orofacial abscesses, cellulitis and sepsis, with resultant high morbidity and even mortality. In the present studies, we developed a novel model of spreading dentoalveolar infections in mice by treatment with neutralizing antibodies against both interleukin-la （IL-1a） and IL-1β. Surprisingly male but not female mice given anti-lL-1 antibodies developed orofacial abscesses, weight loss, splenomegaly and sepsis. Female mice developed abscesses and sepsis comparable to males following ovariectomy （OVX）, which was reversed by estrogen supplementation. Anti-lL-1 blockade inhibited IL-12, interferon y （IFNy） and IL-6 but not IL-IO expression in infrabony lesions, suggestive of a local anti-inflammatory response. There was greater infiltration of neutrophils and other inflammatory ceils into lesions in anti-lL-l-treated animals; however, blood leukocytes had reduced bacterial phagocytic and killing activity ex vivo. Estrogen directly stimulated IL-1 production by macrophages, suggesting that the resistance of females to disseminating dentoalveolar infections may be due to their heightened pro-inflammatory responses following bacterial challenge, leading to enhanced localization of these infections.
基金supported by the National Institute of Dental and Craniofacial Research(NIDCR)the National Center for Research Resources(NCRR)of the National Institutes of Health(NIH)under award numbers R21DE023178,R01DE024796,and S10RR027553
文摘Hypoxia（low oxygen level） is an important feature during infections and affects the host defence mechanisms. The host has evolved specific responses to address hypoxia, which are strongly dependent on the activation of hypoxia-inducible factor 1（HIF-1）.Hypoxia interferes degradation of HIF-1 alpha subunit（HIF-1α）, leading to stabilisation of HIF-1α, heterodimerization with HIF-1 beta subunit（HIF-1β） and subsequent activation of HIF-1 pathway. Apical periodontitis（periapical lesion） is a consequence of endodontic infection and ultimately results in destruction of tooth-supporting tissue, including alveolar bone. Thus far, the role of HIF-1 in periapical lesions has not been systematically examined. In the present study, we determined the role of HIF-1 in a wellcharacterised mouse periapical lesion model using two HIF-1α-activating strategies, dimethyloxalylglycine（DMOG） and adenovirusinduced constitutively active HIF-1α（CA-HIF1 A）. Both DMOG and CA-HIF1 A attenuated periapical inflammation and tissue destruction. The attenuation in vivo was associated with downregulation of nuclear factor-κappa B（NF-κB） and osteoclastic gene expressions. These two agents also suppressed NF-κB activation and subsequent production of proinflammatory cytokines by macrophages. Furthermore, activation of HIF-1α by DMOG specifically suppressed lipopolysaccharide-stimulated macrophage differentiation into M1 cells, increasing the ratio of M2 macrophages against M1 cells. Taken together, our data indicated that activation of HIF-1 plays a protective role in the development of apical periodontitis via downregulation of NF-κB, proinflammatory cytokines, M1 macrophages and osteoclastogenesis.
基金Supported by(in part)Grants UH2CA140233 from the Human Microbiome Project of the NIH Roadmap Initiative and National Cancer InstituteR01AI063477 from the National Institute of Allergy and Infectious Diseases+1 种基金DE-11443 from the National Institute of Dental and Craniofacial ResearchU19DE018385 from the National Institute of Dental & Craniofacial Research
文摘AIM:To design and validate broad-range 16S rRNA primers for use in high throughput sequencing to classify bacteria isolated from the human foregut microbiome.METHODS:A foregut microbiome dataset was constructed using 16S rRNA gene sequences obtained from oral,esophageal,and gastric microbiomes produced by Sanger sequencing in previous studies represented by 219 bacterial species.Candidate primers evaluated were from the European rRNA database.To assess the effect of sequence length on accuracy of classification,16S rRNA genes of various lengths were created by trimming the full length sequences.Sequences spanning various hypervariable regions were selected to simulate the amplicons that would be obtained using possible primer pairs.The sequences were compared with full length 16S rRNA genes for accuracy in taxonomic classification using online software at the Ribosomal Database Project (RDP).The universality of the primer set was evaluated using the RDP 16S rRNA database which is comprised of 433 306 16S rRNA genes,represented by 36 phyla.RESULTS:Truncation to 100 nucleotides(nt)downstream from the position corresponding to base 28 in the Escherichia coli 16S rRNA gene caused misclassification of 87(39.7%)of the 219 sequences,compared with misclassification of only 29(13.2%)sequences with truncation to 350 nt.Among 350-nt sequence reads within various regions of the 16S rRNA gene,the reverse read of an amplicon generated using the 343F/798R primers had the least(8.2%)effect on classification.In comparison,truncation to 900 nt mimicking single pass Sanger reads misclassified 5.0%of the 219 sequences.The 343F/798R amplicon accurately assigned 91.8%of the 219 sequences at the species level.Weighted by abundance of the species in the esophageal dataset,the 343F/798R amplicon yielded similar classification accuracy without a significant loss in species coverage(92%).Modification of the 343F/798R primers to 347F/803R increased their universality among foregut species.Assuming that a typicalpolymerase chain reaction can tolerate 2 mismatches between a primer and a template,the modified 347F and 803R primers should be able to anneal 98%and 99.6%of all 16S rRNA genes in the RDP database.CONCLUSION:347F/803R is the most suitable pair of primers for classification of foregut 16S rRNA genes but also possess universality suitable for analyses of other complex microbiomes.
文摘The role of third molars in the oral cavity has been extensively studied over the years. Literature includes numerous diagnostic and treatment alternatives regarding the third molars. However, an issue that has not been discussed at the same level is their involvement in orthodontic therapy. The aim of this study is to present a review of the contemporary literature regarding the most broadly discussed aspects of the multifactorial role of third molars in orthodontics and which are of general dental interest too.
基金supported by the National Key Research and Development Program of China (2016YFC1102700)the National Natural Science Foundation of China (grant No.: 81771085, 81430011, 81600858, and 81600874)the Key projects of Sichuan Provincial Health and Family planning Commission (grant No.: 16ZD021)
文摘The biodiversity of the mycobiome,an important component of the oral microbial community,and the roles of fungal–bacterial and fungal–immune system interactions in the pathogenesis of oral lichen planus (OLP) remain largely uncharacterized.In this study,we sequenced the salivary mycobiome and bacteriome associated with OLP.First,we described the dysbiosis of the microbiome in OLP patients,which exhibits lower levels of fungi and higher levels of bacteria.Significantly higher abundances of the fungi Candida and Aspergillus in patients with reticular OLP and of Alternaria and Sclerotiniaceae_unidentified in patients with erosive OLP were observed compared to the healthy controls.Aspergillus was identified as an “OLP-associated” fungus because of its detection at a higher frequency than in the healthy controls.Second,the co-occurrence patterns of the salivary mycobiome–bacteriome demonstrated negative associations between specific fungal and bacterial taxa identified in the healthy controls,which diminished in the reticular OLP group and even became positive in the erosive OLP group.Moreover,the oral cavities of OLP patients were colonized by dysbiotic oral flora with lower ecological network complexity and decreased fungal–Firmicutes and increased fungal–Bacteroidetes sub-networks.Third,several keystone fungal genera (Bovista,Erysiphe,Psathyrella,etc.) demonstrated significant correlations with clinical scores and IL-17 levels.Thus,we established that fungal dysbiosis is associated with the aggravation of OLP.Fungal dysbiosis could alter the salivary bacteriome or may reflect a direct effect of host immunity,which participates in OLP pathogenesis.
基金supported by grants from the National Natural Science Foundation of China(81870771)the plan of the talents for Liaoning development(XLYC1802129)。
文摘Abstract:Ulcerative Colitis(UC)has been reported to be related to Porphyromonas gingivalis(P.gingivalis).Porphyromonas gingivalis peptidylarginine deiminase(PPAD),a virulence factor released by P.gingivalis,is known to induce inflammatory responses.To explore the pathological relationships between PPAD and UC,we used homologous recombination technology to construct a P.gingivalis strain in which the PPAD gene was deleted(Δppad)and aΔppad strain in which the PPAD gene was restored(comΔppad).C57 BL/6 mice were orally gavaged with saline,P.gingivalis,Δppad,or comΔppad twice a week for the entire 40 days(days 0-40),and then,UC was induced by dextran sodium sulfate(DSS)solution for 10 days(days 31-40).P.gingivalis and comΔppad exacerbated DDS-induced colitis,which was determined by assessing the parameters of colon length,disease activity index,and histological activity index,butΔppad failed to exacerbate DDS-induced colitis.Flow cytometry and ELISA revealed that compared withΔppad,P.gingivalis,and comΔppad increased T helper 17(Th17)cell numbers and interleukin(IL)-17 production but decreased regulatory T cells(Tregs)numbers and IL-10 production in the spleens of mice with UC.We also cocultured P.gingivalis,Δppad,or comΔppad with T lymphocytes in vitro and found that P.gingivalis and comΔppad significantly increased Th17 cell numbers and decreased Treg cell numbers.Immunofluorescence staining of colon tissue paraffin sections also confirmed these results.The results suggested that P.gingivalis exacerbated the severity of UC in part via PPAD.
基金supported by the Evans Center for Interdisciplinary Biomedical Research ARC on ‘Oral microbiome in AhR activation and oral cancer development and progression’ at Boston University (http://www.bumc.bu.edu/evanscenteribr/)the Forsyth Institute pilot grant programme
文摘Oral squamous cell carcinoma(OSCC) is the most prevalent and most commonly studied oral cancer. However, there is a void regarding the role that the oral microbiome may play in OSCC. Although the relationship between microbial community composition and OSCC has been thoroughly investigated, microbial profiles of the human microbiome in cancer are understudied. Here we performed a small pilot study of community-wide metatranscriptome analysis to profile mRNA expression in the entire oral microbiome in OSCC to reveal molecular functions associated with this disease. Fusobacteria showed a statistically significantly higher number of transcripts at tumour sites and tumour-adjacent sites of cancer patients compared to the healthy controls analysed. Regardless of the community composition, specific metabolic signatures were consistently found in disease. Activities such as iron ion transport, tryptophanase activity, peptidase activities and superoxide dismutase were over-represented in tumour and tumour-adjacent samples when compared to the healthy controls. The expression of putative virulence factors in the oral communities associated with OSCC showed that activities related to capsule biosynthesis, flagellum synthesis and assembly, chemotaxis, iron transport, haemolysins and adhesins were upregulated at tumour sites. Moreover, activities associated with protection against reactive nitrogen intermediates, chemotaxis, flagellar and capsule biosynthesis were also upregulated in non-tumour sites of cancer patients. Although they are preliminary, our results further suggest that Fusobacteria may be the leading phylogenetic group responsible for the increase in expression of virulence factors in the oral microbiome of OSCC patients.
