Background:Benign prostatic hyperplasia(BPH)is the most common disease in elderly men.There is increasing evidence that periodontitis increases the risk of BPH,but the specific mechanism remains unclear.This study aim...Background:Benign prostatic hyperplasia(BPH)is the most common disease in elderly men.There is increasing evidence that periodontitis increases the risk of BPH,but the specific mechanism remains unclear.This study aimed to explore the role and mechanism of the key periodontal pathogen Porphyromonas gingivalis(P.gingivalis)in the development of BPH.Methods:The subgingival plaque(Sp)and prostatic fluid(Pf)of patients with BPH concurrent periodontitis were extracted and cultured for 16S r DNA sequencing.Ligature-induced periodontitis,testosterone-induced BPH and the composite models in rats were established.The P.gingivalis and its toxic factor P.gingivalis lipopolysaccharide(P.gLPS)were injected into the ventral lobe of prostate in rats to simulate its colonization of prostate.P.g-LPS was used to construct the prostate cell infection model for mechanism exploration.Results:P.gingivalis,Streptococcus oralis,Capnocytophaga ochracea and other oral pathogens were simultaneously detected in the Sp and Pf of patients with BPH concurrent periodontitis,and the average relative abundance of P.gingivalis was found to be the highest.P.gingivalis was detected in both Sp and Pf in 62.5%of patients.Simultaneous periodontitis and BPH synergistically aggravated prostate histological changes.P.gingivalis and P.gLPS infection could induce obvious hyperplasia of the prostate epithelium and stroma(epithelial thickness was 2.97-fold and 3.08-fold that of control group,respectively),and increase of collagen fibrosis(3.81-fold and 5.02-fold that of control group,respectively).P.gingivalis infection promoted prostate cell proliferation,inhibited apoptosis,and upregulated the expression of inflammatory cytokines interleukin-6(IL-6;4.47-fold),interleukin-6 receptor-α(IL-6Rα;5.74-fold)and glycoprotein 130(gp130;4.47-fold)in prostatic tissue.P.g-LPS could significantly inhibit cell apoptosis,promote mitosis and proliferation of cells.P.g-LPS activates the Akt pathway through IL-6/IL-6Rα/gp130 complex,which destroys the imbalance between proliferation and apoptosis of prostate cells,induces BPH.Conclusion:P.gingivalis was abundant in the Pf of patients with BPH concurrent periodontitis.P.gingivalis infection can promote BPH,which may affect the progression of BPH via inflammation and the Akt signaling pathway.展开更多
Aim To elucidate the genetic basis for the pronounced resistance that the oral pathogen, Porphyromonas gingivalis （P. gingivalis）, exhibits towards the cationic antimicrobial peptide, polymyxin B. Methodology A gene...Aim To elucidate the genetic basis for the pronounced resistance that the oral pathogen, Porphyromonas gingivalis （P. gingivalis）, exhibits towards the cationic antimicrobial peptide, polymyxin B. Methodology A genetic screen of P. gingivalis clones generated by a Tn4400-based random insertion mutagenesis strategy was performed to identify bacteria harboring novel genetic mutations that render P. gingivalis susceptible to killing by the cationic antimicrobial peptide, polymyxin B （PMB, 50μg·mL^-1）. Results P. gingivalis （ATCC 33277） is unusually resistant to the cationic antimicrobial peptide, PMB at relatively high concentrations （200μg·mL^-1）. Approximately 2,700 independent Tn4400 ＇-derived mutants ofP. gingivalis were examined for increased sensitivity to PMB killing at a relatively low dose （50 μg·mL^-1）. A single PMB-sensitive mutant was obtained in this phenotypic screen. We determined that the Tn4400＇ transposon was integrated into the gene encoding the lipid A 4＇-phosphatase, PGN 0524, demonstrating that this insertion event was responsible for its increased susceptibility of this clone to PMB-dependent killing. The resulting mutant strain, designated 0524-Tn4400＇, was highly sensitive to PMB killing relative to wild-type P. gingivalis, and exhibited the same sensitivity as the previously characterized strain, 0524KO, which bears a genetically engineered deletion in the PGN_0524 locus. Positive ion mass spectrometric structural （MALDI-TOF MS） analyses revealed that lipid A isolates from 0524-Tn4400＂ and 0524KO strains displayed strikingly similar MALDI-TOF MS spectra that were substantially different from the wildtype P gingivalis lipid A spectrum. Finally, intact 0524- Tn4400＇ and 0524KO mutant bacteria, as well as their corresponding LPS isolates, were significantly more potent in stimulating Toll-like receptor 4 （TLR4）-dependent E-selectin expression in human endothelial cells relative to intact wild-type P.. gingivalis or its corresponding LPS isolate. Conclusion The combined molecular evidence provided in this report suggests that PGN 0524, a lipid A 4＇-phosphatase, is the sole genetic element conferring the ability of the periodontopathogen, P. gingivalis, to evade the killing activity of cationic antimicrobial peptides, such as PMB. These data strongly implicate PGN_0524 as a critical virulence factor for the ability of P.. gingivalis to evade front-line host innate defenses that are dependent upon cationic antimicrobial peptide activity and TLR 4 sensing.展开更多
Matrix metalloproteinase-9 (MMP-9) is a highly glycosylated endopeptidase implicated in a wide rage of oral mucosal inflammatory and neoplastic diseases, including chronic periodontitis, a persistent mucosal inflammat...Matrix metalloproteinase-9 (MMP-9) is a highly glycosylated endopeptidase implicated in a wide rage of oral mucosal inflammatory and neoplastic diseases, including chronic periodontitis, a persistent mucosal inflammation attributed primarily to infection by oral anaerobe, P. gingivalis. In this study, we explored the role of Rac1 and mitogen-activated protein kinases (MAPKs) in the processes of MMP-9 release in sublingual salivary gland cells exposed to P. gingivalis key endotoxin, cell wall lipopolysaccharide (LPS). We demonstrate that the LPS-elicited induction in the acinar cell MMP-9 release is associated with MAPK, ERK and p38 activation, and occurs with the involvement of Rac1 and cytosolic phospholipase A<sub>2</sub> (cPLA<sub>2</sub>). Further, we reveal that the LPS-induced MMP-9 release involves ERK-mediated phosphorylation of cPLA<sub>2</sub> on Ser<sup>505</sup> that is essential for its membrane translocation with Rac1, and that this process requires p38 activation. Moreover, we show that phosphorylation and membrane localization of p38 with Rac1-GTP play a pivotal role in cPLA<sub>2</sub>-dependent induction in MMP-9 release. Thus collectively, our findings infer that P. gingivalis LPS-induced up-regulation in the acinar cell MMP-9 release requires ERK-dependent recruitment of cPLA<sub>2</sub> to the membrane localized Rac1/p38 complex.展开更多
Alzheimer’s disease has proven to be largely intractable to treatment,despite years of research,and numerous trials of therapies that target the hallmarks of the disease-amyloid plaques and neurofibrillary tangles.Th...Alzheimer’s disease has proven to be largely intractable to treatment,despite years of research,and numerous trials of therapies that target the hallmarks of the disease-amyloid plaques and neurofibrillary tangles.The etiology of Alzheimer’s disease remains elusive.There is a growing body of evidence for an infectious trigger of Alzheimer’s disease,and,in particular,the focus has been on the oral pathogen Porphyromonas gingivalis(P.gingivalis).Reports of the expression of a misfolded form of p53 in non-neuronal cells(fibroblasts,peripheral blood mononuclear cells,and B cells)and serum,which appears several years before clinical symptoms manifest,may provide further support for the role of bacteria in general,and P.gingivalis in particular,in the initiation of the disease.This review presents a model of the pathway from initial oral infection with P.gingivalis to amyloid plaque formation and neuronal degeneration,via the steps of chronic periodontitis;secretion of the inflammagens lipopolysaccharide and gingipains into the bloodstream;induction of an inflammatory response in both peripheral cells and tissues;disruption of the blood-brain barrier,and entry into the central nervous system of the inflammagens and the P.gingivalis bacteria themselves.In this model,the misfolded p53(or“unfolded p53”;up53)is induced in non-neuronal cells and upregulated in serum as a result of oxidative stress due to lipopolysaccharide from P.gingivalis.up53 is therefore a potential biomarker for early diagnosis of the presence of a causative agent of Alzheimer’s disease.Fastidious dental hygiene and aggressive antibiotic treatment may prevent the patient progressing to clinical Alzheimer’s disease if serum up53 is detected at this pre-symptomatic stage.展开更多
This article aims to explain the inhibitory mechanism of thinned-young apple polyphenols(YAP)toward Fusobacterium nucleatum(F.nucleatum),Porphyromonas gingivalis(P.gingivalis)and Prevotella intermedia(P.intermedia).YA...This article aims to explain the inhibitory mechanism of thinned-young apple polyphenols(YAP)toward Fusobacterium nucleatum(F.nucleatum),Porphyromonas gingivalis(P.gingivalis)and Prevotella intermedia(P.intermedia).YAP has optimal antibacterial concentration against F.nucleatum(10.00 mg/mL),P.gingivalis(8.00 mg/mL)and P.intermedia(8.00 mg/mL),with viability of 47.97%,38.01%and 36.94%,respectively.Scanning electron microscopy(SEM)and confocal laser scanning microscopy(CLSM)observation revealed that YAP could cause the morphological changes of the halitosis-related bacterial cells and induce cell apoptosis.With the increase of YAP treatment concentrations,the permeability of the outer membranes(OM)and inner membranes(IM)of halitosis-related bacteria dramatically increased,resulting in the release of proteins and nucleic acids.In addition,bacterial cell membrane potential(MP)decreased after exposure to YAP.The results of this study provide new antibacterial agents for halitosis-related bacteria and find a new way for the development of thinned-young apples.展开更多
基金supported(in part)by the National Natural Science Foundation of China(82200862,82370778)the Hubei Provincial Natural Science Foundation(2022CFB681,2023AFA061,2019CFB760)+4 种基金the Hubei Province Health and Family Planning Scientific Research Project(WJ2023M058,WJ2019H035)the Key Scientific Research Project of Education Department of Henan Province(22A320038)the Fundamental Research Funds for the Central Universities(2042023kf1019,2042023kf0051,2042022kf0072)the Zhongnan Hospital of Wuhan University,Science Technology and Innovation Seed Fund(CXPY2022074)the Young Top-notch Talent Cultivation Program of Hubei Province(for Prof.Zeng XT).
文摘Background:Benign prostatic hyperplasia(BPH)is the most common disease in elderly men.There is increasing evidence that periodontitis increases the risk of BPH,but the specific mechanism remains unclear.This study aimed to explore the role and mechanism of the key periodontal pathogen Porphyromonas gingivalis(P.gingivalis)in the development of BPH.Methods:The subgingival plaque(Sp)and prostatic fluid(Pf)of patients with BPH concurrent periodontitis were extracted and cultured for 16S r DNA sequencing.Ligature-induced periodontitis,testosterone-induced BPH and the composite models in rats were established.The P.gingivalis and its toxic factor P.gingivalis lipopolysaccharide(P.gLPS)were injected into the ventral lobe of prostate in rats to simulate its colonization of prostate.P.g-LPS was used to construct the prostate cell infection model for mechanism exploration.Results:P.gingivalis,Streptococcus oralis,Capnocytophaga ochracea and other oral pathogens were simultaneously detected in the Sp and Pf of patients with BPH concurrent periodontitis,and the average relative abundance of P.gingivalis was found to be the highest.P.gingivalis was detected in both Sp and Pf in 62.5%of patients.Simultaneous periodontitis and BPH synergistically aggravated prostate histological changes.P.gingivalis and P.gLPS infection could induce obvious hyperplasia of the prostate epithelium and stroma(epithelial thickness was 2.97-fold and 3.08-fold that of control group,respectively),and increase of collagen fibrosis(3.81-fold and 5.02-fold that of control group,respectively).P.gingivalis infection promoted prostate cell proliferation,inhibited apoptosis,and upregulated the expression of inflammatory cytokines interleukin-6(IL-6;4.47-fold),interleukin-6 receptor-α(IL-6Rα;5.74-fold)and glycoprotein 130(gp130;4.47-fold)in prostatic tissue.P.g-LPS could significantly inhibit cell apoptosis,promote mitosis and proliferation of cells.P.g-LPS activates the Akt pathway through IL-6/IL-6Rα/gp130 complex,which destroys the imbalance between proliferation and apoptosis of prostate cells,induces BPH.Conclusion:P.gingivalis was abundant in the Pf of patients with BPH concurrent periodontitis.P.gingivalis infection can promote BPH,which may affect the progression of BPH via inflammation and the Akt signaling pathway.
文摘Aim To elucidate the genetic basis for the pronounced resistance that the oral pathogen, Porphyromonas gingivalis （P. gingivalis）, exhibits towards the cationic antimicrobial peptide, polymyxin B. Methodology A genetic screen of P. gingivalis clones generated by a Tn4400-based random insertion mutagenesis strategy was performed to identify bacteria harboring novel genetic mutations that render P. gingivalis susceptible to killing by the cationic antimicrobial peptide, polymyxin B （PMB, 50μg·mL^-1）. Results P. gingivalis （ATCC 33277） is unusually resistant to the cationic antimicrobial peptide, PMB at relatively high concentrations （200μg·mL^-1）. Approximately 2,700 independent Tn4400 ＇-derived mutants ofP. gingivalis were examined for increased sensitivity to PMB killing at a relatively low dose （50 μg·mL^-1）. A single PMB-sensitive mutant was obtained in this phenotypic screen. We determined that the Tn4400＇ transposon was integrated into the gene encoding the lipid A 4＇-phosphatase, PGN 0524, demonstrating that this insertion event was responsible for its increased susceptibility of this clone to PMB-dependent killing. The resulting mutant strain, designated 0524-Tn4400＇, was highly sensitive to PMB killing relative to wild-type P. gingivalis, and exhibited the same sensitivity as the previously characterized strain, 0524KO, which bears a genetically engineered deletion in the PGN_0524 locus. Positive ion mass spectrometric structural （MALDI-TOF MS） analyses revealed that lipid A isolates from 0524-Tn4400＂ and 0524KO strains displayed strikingly similar MALDI-TOF MS spectra that were substantially different from the wildtype P gingivalis lipid A spectrum. Finally, intact 0524- Tn4400＇ and 0524KO mutant bacteria, as well as their corresponding LPS isolates, were significantly more potent in stimulating Toll-like receptor 4 （TLR4）-dependent E-selectin expression in human endothelial cells relative to intact wild-type P.. gingivalis or its corresponding LPS isolate. Conclusion The combined molecular evidence provided in this report suggests that PGN 0524, a lipid A 4＇-phosphatase, is the sole genetic element conferring the ability of the periodontopathogen, P. gingivalis, to evade the killing activity of cationic antimicrobial peptides, such as PMB. These data strongly implicate PGN_0524 as a critical virulence factor for the ability of P.. gingivalis to evade front-line host innate defenses that are dependent upon cationic antimicrobial peptide activity and TLR 4 sensing.
文摘Matrix metalloproteinase-9 (MMP-9) is a highly glycosylated endopeptidase implicated in a wide rage of oral mucosal inflammatory and neoplastic diseases, including chronic periodontitis, a persistent mucosal inflammation attributed primarily to infection by oral anaerobe, P. gingivalis. In this study, we explored the role of Rac1 and mitogen-activated protein kinases (MAPKs) in the processes of MMP-9 release in sublingual salivary gland cells exposed to P. gingivalis key endotoxin, cell wall lipopolysaccharide (LPS). We demonstrate that the LPS-elicited induction in the acinar cell MMP-9 release is associated with MAPK, ERK and p38 activation, and occurs with the involvement of Rac1 and cytosolic phospholipase A<sub>2</sub> (cPLA<sub>2</sub>). Further, we reveal that the LPS-induced MMP-9 release involves ERK-mediated phosphorylation of cPLA<sub>2</sub> on Ser<sup>505</sup> that is essential for its membrane translocation with Rac1, and that this process requires p38 activation. Moreover, we show that phosphorylation and membrane localization of p38 with Rac1-GTP play a pivotal role in cPLA<sub>2</sub>-dependent induction in MMP-9 release. Thus collectively, our findings infer that P. gingivalis LPS-induced up-regulation in the acinar cell MMP-9 release requires ERK-dependent recruitment of cPLA<sub>2</sub> to the membrane localized Rac1/p38 complex.
文摘Alzheimer’s disease has proven to be largely intractable to treatment,despite years of research,and numerous trials of therapies that target the hallmarks of the disease-amyloid plaques and neurofibrillary tangles.The etiology of Alzheimer’s disease remains elusive.There is a growing body of evidence for an infectious trigger of Alzheimer’s disease,and,in particular,the focus has been on the oral pathogen Porphyromonas gingivalis(P.gingivalis).Reports of the expression of a misfolded form of p53 in non-neuronal cells(fibroblasts,peripheral blood mononuclear cells,and B cells)and serum,which appears several years before clinical symptoms manifest,may provide further support for the role of bacteria in general,and P.gingivalis in particular,in the initiation of the disease.This review presents a model of the pathway from initial oral infection with P.gingivalis to amyloid plaque formation and neuronal degeneration,via the steps of chronic periodontitis;secretion of the inflammagens lipopolysaccharide and gingipains into the bloodstream;induction of an inflammatory response in both peripheral cells and tissues;disruption of the blood-brain barrier,and entry into the central nervous system of the inflammagens and the P.gingivalis bacteria themselves.In this model,the misfolded p53(or“unfolded p53”;up53)is induced in non-neuronal cells and upregulated in serum as a result of oxidative stress due to lipopolysaccharide from P.gingivalis.up53 is therefore a potential biomarker for early diagnosis of the presence of a causative agent of Alzheimer’s disease.Fastidious dental hygiene and aggressive antibiotic treatment may prevent the patient progressing to clinical Alzheimer’s disease if serum up53 is detected at this pre-symptomatic stage.
基金supported by the National Natural Science Foundation of China(No.31701563)the Key Research and Development Program of Shaanxi Province(No.2019NY-124)+1 种基金Ministry of Education(XGZX 2021G08)the Fundamental Research Funds for the Central Universities at Shaanxi Normal University(1301031057).
文摘This article aims to explain the inhibitory mechanism of thinned-young apple polyphenols(YAP)toward Fusobacterium nucleatum(F.nucleatum),Porphyromonas gingivalis(P.gingivalis)and Prevotella intermedia(P.intermedia).YAP has optimal antibacterial concentration against F.nucleatum(10.00 mg/mL),P.gingivalis(8.00 mg/mL)and P.intermedia(8.00 mg/mL),with viability of 47.97%,38.01%and 36.94%,respectively.Scanning electron microscopy(SEM)and confocal laser scanning microscopy(CLSM)observation revealed that YAP could cause the morphological changes of the halitosis-related bacterial cells and induce cell apoptosis.With the increase of YAP treatment concentrations,the permeability of the outer membranes(OM)and inner membranes(IM)of halitosis-related bacteria dramatically increased,resulting in the release of proteins and nucleic acids.In addition,bacterial cell membrane potential(MP)decreased after exposure to YAP.The results of this study provide new antibacterial agents for halitosis-related bacteria and find a new way for the development of thinned-young apples.
