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Journal of Alzheimer's Disease : JAD 2020Microbial agents including periodontal pathogens have recently appeared as important actors in Alzheimer's disease (AD) pathology. We examined associations of clinical...
Microbial agents including periodontal pathogens have recently appeared as important actors in Alzheimer's disease (AD) pathology. We examined associations of clinical periodontal and bacterial parameters with incident all-cause and AD dementia as well as AD mortality among US middle-aged and older adults. Clinical [Attachment Loss (AL); probing pocket depth (PPD)] and bacterial [pathogen immunoglobulin G (IgG)] periodontal markers were investigated in relation to AD and all-cause dementia incidence and to AD mortality, using data from the third National Health and Nutrition Examination Surveys (NHANES III, 1988-1994) linked longitudinally with National Death Index and Medicare data through January 1, 2014, with up to 26 years of follow-up. Sex- and age-specific multivariable-adjusted Cox proportional hazards models were conducted. Among those ≥65 years, AD incidence and mortality were consistently associated with PPD, two factors and one cluster comprised of IgG titers against Porphyromonas gingivalis (P. gingivalis), Prevotella melaninogenica (P. melaninogenica) and Campylobacter rectus (C. rectus) among others. Specifically, AD incidence was linked to a composite of C. rectus and P. gingivalis titers (per SD, aHR = 1.22; 95% CI, 1.04-1.43, p = 0.012), while AD mortality risk was increased with another composite (per SD, aHR = 1.46; 95% CI, 1.09-1.96, p = 0.017) loading highly on IgG for P. gingivalis, Prevotella intermedia, Prevotella nigrescens, Fusobacterium nucleatum, C. rectus, Streptococcus intermedius, Capnocylophaga Ochracea, and P. melaninogenica. This study provides evidence for an association between periodontal pathogens and AD, which was stronger for older adults. Effectiveness of periodontal pathogen treatment on reducing sequelae of neurodegeneration should be tested in randomized controlled trials.
Topics: Aged; Alzheimer Disease; Campylobacter rectus; Dementia; Female; Health Surveys; Humans; Incidence; Male; Middle Aged; Periodontitis; Porphyromonas gingivalis; Prevotella melaninogenica; United States
PubMed: 32280099
DOI: 10.3233/JAD-200064 -
Advanced Science (Weinheim,... May 2022Bile reflux gastritis (BRG) is associated with the development of gastric cancer (GC), but the specific mechanism remains elusive. Here, a comprehensive study is...
Bile reflux gastritis (BRG) is associated with the development of gastric cancer (GC), but the specific mechanism remains elusive. Here, a comprehensive study is conducted to explore the roles of refluxed bile acids (BAs) and microbiome in gastric carcinogenesis. The results show that conjugated BAs, interleukin 6 (IL-6), lipopolysaccharide (LPS), and the relative abundance of LPS-producing bacteria are increased significantly in the gastric juice of both BRG and GC patients. A secondary BA, taurodeoxycholic acid (TDCA), is significantly and positively correlated with the LPS-producing bacteria in the gastric juice of these patients. TDCA promotes the proliferation of normal gastric epithelial cells (GES-1) through activation of the IL-6/JAK1/STAT3 pathway. These results are further verified in two mouse models, one by gavage of TDCA, LPS, and LPS-producing bacteria (Prevotella melaninogenica), respectively, and the other by bile reflux (BR) surgery, mimicking clinical bile refluxing. Moreover, the bile reflux induced gastric precancerous lesions observed in the post BR surgery mice can be prevented by treatment with cryptotanshinone, a plant-derived STAT3 inhibitor. These results reveal an important underlying mechanism by which bile reflux promotes gastric carcinogenesis and provide an alternative strategy for the prevention of GC associated with BRG.
Topics: Animals; Bile Reflux; Carcinogenesis; Gastritis; Gastrointestinal Microbiome; Humans; Interleukin-6; Lipopolysaccharides; Mice; Stomach Neoplasms; Taurodeoxycholic Acid
PubMed: 35285172
DOI: 10.1002/advs.202200263 -
Leukemia May 2023Multiple Myeloma (MM) remains an incurable plasma cell neoplasm. Although little is known about the etiology of MM, several metabolic risk factors such as obesity,... (Review)
Review
Multiple Myeloma (MM) remains an incurable plasma cell neoplasm. Although little is known about the etiology of MM, several metabolic risk factors such as obesity, diabetes mellitus, diet, and the human intestinal microbiome have been linked to the pathogenesis of MM. In this article, we provide a detailed review of dietary and microbiome factors involved in the pathogenesis of MM and their impact on outcomes. Concurrent with treatment advancements that have improved survival in MM, focused efforts are needed to reduce the burden of MM as well as improve MM specific and overall outcomes once MM is diagnosed. The findings presented in this review will provide a comprehensive guide on the evidence available to date of the impact of dietary and other lifestyle interventions on the gut microbiome and on MM incidence, outcomes, and quality of life. Data generated from such studies can help formulate evidence-based guidelines for healthcare providers to counsel individuals at risk such as those with Monoclonal Gammopathy of Undetermined Significance (MGUS) and Smoldering Multiple Myeloma (SMM) as well as MM survivors with respect to their dietary habits.
Topics: Humans; Multiple Myeloma; Plasma Cells; Quality of Life; Paraproteinemias; Diet; Microbiota
PubMed: 36997677
DOI: 10.1038/s41375-023-01874-4 -
Frontiers in Microbiology 2021is recognized as one of the core anaerobic genera in the oral microbiome. In addition, members of this genus belong to microbial communities of the gastrointestinal and... (Review)
Review
is recognized as one of the core anaerobic genera in the oral microbiome. In addition, members of this genus belong to microbial communities of the gastrointestinal and respiratory tracts. Several novel species, most of them of oral origin, have been described, but limited knowledge is still available of their clinical relevance. is among the anaerobic commensals on oral mucosae from early months of life onward, and other early colonizing species in the oral cavity include and . Oral species get constant access to the gastrointestinal tract via saliva swallowing and to lower airways via microaspiration. At these extra-oral sites, they play a role as commensals but also as potentially harmful agents on mucosal surfaces. The aim of this narrative review is to give an updated overview on the involvement of oral species in gastrointestinal and respiratory health and disease.
PubMed: 35069501
DOI: 10.3389/fmicb.2021.798763 -
Clinical and Experimental Immunology Aug 2022Oral lichen planus (OLP) is a common chronic inflammatory disease occurring in the oral mucosa. Bacteria are a key driver of mucosal immune responses and can induce...
Oral lichen planus (OLP) is a common chronic inflammatory disease occurring in the oral mucosa. Bacteria are a key driver of mucosal immune responses and can induce changes in gene expression and function of epithelial keratinocytes. IL-36γ can induce the expression of antimicrobial peptides, cytokines, and chemokines, and is widely involved in many chronic inflammatory diseases. Our aim is to explore the role of IL-36γ in the pathological process of OLP when Prevotella melaninogenica (P. melaninogenica) invades the oral mucosa. The expression of IL-36γ in OLP lesions and mice was detected by immunohistochemistry. Recombinant human IL-36Gamma (rhIL-36γ) was used to treat oral keratinocytes and the expression levels of inflammatory cytokines were detected by qRT-PCR and ELISA. The expression of IL-36γ and TRPV1 was detected by western blotting following co-culturing P. melaninogenica with oral keratinocytes. The mRNA expression of IL-36γ was detected by qRT-PCR. From our results, IL-36γ was upregulated in OLP lesions. Exogenous rhIL-36γ promoted the expression of pro-inflammatory cytokines and antibacterial peptides in oral keratinocytes. The expression of IL-36γ was significantly increased following the stimulation of P. melaninogenica in oral keratinocytes and mice. TRPV1 activation was induced by P. melaninogenica and its activation enhanced the expression of IL-36γ. IL-36Ra could reduce the inflammation in OLP in vitro. In summary, overexpression of IL-36γ in OLP lesions could promote its pathogenesis by inducing inflammation. P. melaninogenica invasion of oral keratinocytes could induce the expression of IL-36γ by the activation of TRPV1, thereby regulating the interaction between bacteria and oral epithelial cells.
Topics: Animals; Cytokines; Humans; Inflammation; Keratinocytes; Lichen Planus, Oral; Mice; Prevotella melaninogenica
PubMed: 35605143
DOI: 10.1093/cei/uxac054 -
Pathogens (Basel, Switzerland) Sep 2023Oral microbiome disruptions in periodontitis are related to the chronic inflammatory reactions that could in turn lead to the development of multiple oral diseases. The...
Oral microbiome disruptions in periodontitis are related to the chronic inflammatory reactions that could in turn lead to the development of multiple oral diseases. The objective of the study was to assess the frequencies of , , and in oral benign lesions, oral potentially malignant disorders (OPMDs), and oral squamous cell carcinomas (OSCCs) and investigate the impact of these bacteria on the expression patterns of the selected (potential) target genes (//, /, and ). After sample collection (25 benign lesions, 30 OPMDs, and 35 OSCCs) and DNA/RNA extraction, quantitative real-time polymerase chain reaction (qPCR) was performed to detect bacterial presence and assess relative gene expression levels in different lesion groups. was the most prevalent of the three analyzed bacteria, with the frequency being 60% in benign lesions, 87% in OPMDs ( = 0.024), and 77% in OSCC. The OPMD tissues in which was present exhibited a higher expression level of ( = 0.042). Significantly lower expression of was observed in OSCC tissues containing ( = 0.011). The obtained results indicate a substantial contribution of and in the pathogenesis of oral mucosal lesions, possibly via upregulation and downregulation.
PubMed: 37887710
DOI: 10.3390/pathogens12101194 -
Journal of Oral Microbiology 2022Oral are known as anaerobic commensals on oral mucosae and in dental plaques from early life onwards, including pigmented and and non-pigmented species. Many... (Review)
Review
Oral are known as anaerobic commensals on oral mucosae and in dental plaques from early life onwards, including pigmented and and non-pigmented species. Many species contribute to oral inflammatory processes, being frequent findings in dysbiotic biofilms of periodontal diseases (), cariotic lesions ( (formerly ) ), endodontic infections (), and other clinically relevant oral conditions. Over the years, several novel species have been recovered from the oral cavity without knowledge of their clinical relevance. Within this wide genus, virulence properties and other characteristics like biofilm formation seemingly vary in a species- and strain-dependent manner, as shown for the group organisms (, and ). Oral species are identified in various non-oral infections and chronic pathological conditions. Here, we have updated the knowledge of the genus and the role of species as residents and infectious agents of the oral cavity, as well as their detection in non-oral infections, but also gathered information on their potential link to cancers of the head and neck, and other systemic disorders.
PubMed: 36393976
DOI: 10.1080/20002297.2022.2079814 -
Antibiotics (Basel, Switzerland) Jul 2022The genus is a normal constituent of the oral microbiota, and is commonly isolated from mechanically treated polymicrobial infections. However, antibiotic treatment is...
The genus is a normal constituent of the oral microbiota, and is commonly isolated from mechanically treated polymicrobial infections. However, antibiotic treatment is necessary for some patients. This study compared the antibiotic susceptibility and the presence of resistance genes in clinical oral isolates of , , and . Antibiotic susceptibility was assessed using the agar dilution method. PCR confirmed the species and resistance gene frequency in the species. The frequencies of species , , and were 30.2%, 45.7%, and 24.1%, respectively. No isolates of were resistant to amoxicillin/clavulanic acid, tetracycline, or clindamycin. and were resistant to amoxicillin/clavulanic acid and tetracycline at frequencies of 40% and 20%, respectively. was resistant to metronidazole at a frequency of 30%, at 20%, and at 40%. and were resistant to 50% and 10% clindamycin, respectively. The gene most frequently detected was , at 43.3%, followed by at 36.6%, at 26.6%, at 20%, , , and at 16.6%, and at 3.3%. was the species with the highest resistance to antibiotics such as amoxicillin/clavulanic acid, amoxicillin, and clindamycin, in addition to being the species with the largest number of genes compared to and
PubMed: 35884141
DOI: 10.3390/antibiotics11070888 -
Microbial Genomics Feb 2022Cystic fibrosis (CF) and chronic obstructive pulmonary disease (COPD) are characterized by increasingly frequent acute pulmonary exacerbations that reduce life quality...
Cystic fibrosis (CF) and chronic obstructive pulmonary disease (COPD) are characterized by increasingly frequent acute pulmonary exacerbations that reduce life quality and length. Human airways are home to a rich polymicrobial environment, which includes members of the obligately anaerobic genus . Despite their commonness, surprisingly little is known about the prevalence, role, genomic diversity and antimicrobial resistance (AMR) potential of species and strains in healthy and diseased airways. Here, we used comparative genomics to develop a real-time PCR assay to permit rapid species identification and quantification from cultures and clinical specimens. Assay specificity was validated across a panel of and non- species, followed by PCR screening of CF and COPD respiratory-derived cultures. Next, 35 PCR-positive isolates were subjected to whole-genome sequencing. Of eight identified species, , , , and overlapped between participant cohorts. Phylogenomic analysis revealed considerable interhost but limited intrahost diversity, suggesting patient-specific lineages in the lower airways, probably from oral cavity aspirations. Correlation of phenotypic AMR profiles with AMR genes identified excellent correlation between presence and decreased doxycycline susceptibility, and presence and decreased azithromycin susceptibility and clindamycin resistance. AMR rates were higher in the CF isolates, reflecting greater antibiotic use in this cohort. All tested isolates were tobramycin-resistant, providing a potential selection method to improve culture retrieval rates. Our addition of 35 airway-derived genomes to public databases will enhance ongoing efforts to unravel the role of this diverse and enigmatic genus in both diseased and healthy lungs.
Topics: Anti-Bacterial Agents; Cystic Fibrosis; Drug Resistance, Bacterial; Genomics; Humans; Lung; Microbial Sensitivity Tests; Prevotella; Pulmonary Disease, Chronic Obstructive; Sputum
PubMed: 35113778
DOI: 10.1099/mgen.0.000754 -
Journal of Indian Society of... 2023is a Gram-negative anaerobic bacilli. The phenotypic characteristics of the various species of are similar, which often makes it difficult in routine differentiation...
Simultaneous detection and evaluation of , and in subgingival plaque samples of chronic periodontitis and healthy individuals through multiplex polymerase chain reaction.
BACKGROUND
is a Gram-negative anaerobic bacilli. The phenotypic characteristics of the various species of are similar, which often makes it difficult in routine differentiation and identification of all the species.
AIM
The purpose of the study was to detect and compare presence of , and in subgingival plaque samples of chronic periodontitis and healthy individuals.
MATERIALS AND METHODS
Two hundred and thirty-six subjects were considered consisting of chronic periodontitis (128) and healthy (108) individuals. Subgingival plaque sample was collected in reduced transport fluid and analyzed. DNA extraction and polymerase chain reaction (PCR) were performed for genus followed by positive samples were considered for the detection of selected species through multiplex PCR using specific primers.
RESULTS
Out of 236 samples, 94.1% were positive for genus . Out of 222 cases showed the highest number of cases positive (59.5%) followed by (57.2%), (55.4%), and (40.1%). Species were analyzed individually between chronic periodontitis and healthy, , and showed greater positivity in healthy compared to chronic periodontitis. Positivity for was high in chronic periodontitis compared to healthy.
CONCLUSION
The number of positive cases for species, when correlated with clinical parameters showed an increase in mean score for all clinical parameters assessed, suggesting the presence of variation in the prevalence of species and geographic variation do exist in oral microflora. Findings suggest that they can be normal commensals and opportunistic.
PubMed: 37346862
DOI: 10.4103/jisp.jisp_154_22