Oral Microbiota and Salivary Levels of Oral Pathogens in Gastro-Intestinal Diseases: Current Knowledge and Exploratory Study

Various bi-directional associations exist between oral health and gastro-intestinal diseases. The oral microbiome plays a role in the gastro-intestinal carcinogenesis and fusobacteria are the most investigated bacteria involved. This paper aims to review the current knowledge and report the preliminary data on salivary levels of Fusobacterium nucleatum, Porphyromonas gingivalis and Candida albicans in subjects with different gastro-intestinal conditions or pathologies, in order to determine any differences. The null hypothesis was “subjects with different gastro-intestinal diseases do not show significant differences in the composition of the oral microbiota”. Twenty-one subjects undergoing esophagastroduodenoscopy or colonscopy were recruited. For each subject, a salivary sample was collected before the endoscopy procedure, immediately stored at -20°C and subsequently used for genomic bacterial DNA extraction by real-time PCR. Low levels of F. nucleatum and P. gingivalis were peculiar in the oral microbiota in subjects affected by Helicobater pylori-negative chronic gastritis without cancerization and future studies will elucidate this association. The level of C. albicans did not statistically differ among groups. This preliminary study could be used in the future, following further investigation, as a non-invasive method for the search of gastrointestinal diseases and associated markers.

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Oral microbial dysbiosis and its performance in predicting oral cancer

Carcinogenesis ◽

10.1093/carcin/bgaa062 ◽

2020 ◽

Author(s):

Shih-Chi Su ◽

Lun-Ching Chang ◽

Hsien-Da Huang ◽

Chih-Yu Peng ◽

Chun-Yi Chuang ◽

...

Keyword(s):

Oral Cancer ◽

Fusobacterium Nucleatum ◽

Risky Behaviors ◽

Health Condition ◽

Oral Microbiome ◽

Oral Microbiota ◽

Microbial Dysbiosis ◽

Anti Cancer ◽

Betel Quid Chewing ◽

Male Patients

Abstract Dysbiosis of oral microbiome may dictate the progression of oral squamous cell carcinoma (OSCC). Yet, the composition of oral microbiome fluctuates by saliva and distinct sites of oral cavity and is affected by risky behaviors (smoking, drinking and betel quid chewing) and individuals’ oral health condition. To characterize the disturbances in the oral microbial population mainly due to oral tumorigenicity, we profiled the bacteria within the surface of OSCC lesion and its contralateral normal tissue from discovery (n = 74) and validation (n = 42) cohorts of male patients with cancers of the buccal mucosa. Significant alterations in the bacterial diversity and relative abundance of specific oral microbiota (most profoundly, an enrichment for genus Fusobacterium and the loss of genus Streptococcus in the tumor sites) were identified. Functional prediction of oral microbiome shown that microbial genes related to the metabolism of terpenoids and polyketides were differentially enriched between the control and tumor groups, indicating a functional role of oral microbiome in formulating a tumor microenvironment via attenuated biosynthesis of secondary metabolites with anti-cancer effects. Furthermore, the vast majority of microbial signatures detected in the discovery cohort was generalized well to the independent validation cohort, and the clinical validity of these OSCC-associated microbes was observed and successfully replicated. Overall, our analyses reveal signatures (a profusion of Fusobacterium nucleatum CTI-2 and a decrease in Streptococcus pneumoniae) and functions (decreased production of tumor-suppressive metabolites) of oral microbiota related to oral cancer.

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Human oral microbiome and prospective risk for pancreatic cancer: a population-based nested case-control study

Gut ◽

10.1136/gutjnl-2016-312580 ◽

2016 ◽

Vol 67 (1) ◽

pp. 120-127 ◽

Cited By ~ 177

Author(s):

Xiaozhou Fan ◽

Alexander V Alekseyenko ◽

Jing Wu ◽

Brandilyn A Peters ◽

Eric J Jacobs ◽

...

Keyword(s):

Pancreatic Cancer ◽

Case Control Study ◽

Case Control ◽

Oral Microbiome ◽

Rrna Gene ◽

Oral Microbiota ◽

Increased Risk ◽

Oral Pathogens ◽

Nested Case Control ◽

Control Study

ObjectiveA history of periodontal disease and the presence of circulating antibodies to selected oral pathogens have been associated with increased risk of pancreatic cancer; however, direct relationships of oral microbes with pancreatic cancer have not been evaluated in prospective studies. We examine the relationship of oral microbiota with subsequent risk of pancreatic cancer in a large nested case–control study.DesignWe selected 361 incident adenocarcinoma of pancreas and 371 matched controls from two prospective cohort studies, the American Cancer Society Cancer Prevention Study II and the National Cancer Institute Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial. From pre-diagnostic oral wash samples, we characterised the composition of the oral microbiota using bacterial 16S ribosomal RNA (16S rRNA) gene sequencing. The associations between oral microbiota and risk of pancreatic cancer, controlling for the random effect of cohorts and other covariates, were examined using traditional and L1-penalised least absolute shrinkage and selection operator logistic regression.ResultsCarriage of oral pathogens, Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans, were associated with higher risk of pancreatic cancer (adjusted OR for presence vs absence=1.60 and 95% CI 1.15 to 2.22; OR=2.20 and 95% CI 1.16 to 4.18, respectively). Phylum Fusobacteria and its genus Leptotrichia were associated with decreased pancreatic cancer risk (OR per per cent increase of relative abundance=0.94 and 95% CI 0.89 to 0.99; OR=0.87 and 95% CI 0.79 to 0.95, respectively). Risks related to these phylotypes remained after exclusion of cases that developed within 2 years of sample collection, reducing the likelihood of reverse causation in this prospective study.ConclusionsThis study provides supportive evidence that oral microbiota may play a role in the aetiology of pancreatic cancer.

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Oral, intestinal, and pancreatic microbiomes are correlated and exhibit co-abundance in patients with pancreatic cancer and other gastrointestinal diseases

10.1101/2020.01.30.20019752 ◽

2020 ◽

Cited By ~ 1

Author(s):

Mei Chung ◽

Naisi Zhao ◽

Richard Meier ◽

Devin C. Koestler ◽

Erika Del Castillo ◽

...

Keyword(s):

Pancreatic Tumor ◽

Bacterial Species ◽

Fusobacterium Nucleatum ◽

Gastrointestinal Diseases ◽

Pancreatic Tissue ◽

Kappa Statistics ◽

Oral Microbiota ◽

Correlation Networks ◽

Complex Correlation ◽

High Throughput Dna Sequencing

AbstractOral microbiota are believed to play important roles in systemic diseases, including cancer. We collected oral swabs and at least one pancreatic tissue or intestinal samples from 52 subjects, and characterized 16S ribosomal RNA genes using high-throughput DNA sequencing in a total 324 samples. We identified a total of 73 unique Amplicon Sequence Variants (ASVs) that were shared between oral and pancreatic or intestinal samples. Accounting for pairing and within-subject correlation, 7 ASVs showed significant concordance (Kappa statistics) and 5 ASVs exhibited significant or marginally significant Pairwise Stratified Association (PASTA) between oral samples and pancreatic tissue or intestinal samples. Of these, two specific bacterial species (Gemella morbillorum and Fusobacterium nucleatum subsp. vincentii) showed consistent presence or absence patterns between oral and intestinal or pancreatic samples. Lastly, our microbial co-abundance analyses showed several distinct ASVs clusters and complex correlation-networks between ASV clusters in buccal, saliva, duodenum, jejunum, and pancreatic tumor samples. Toghether, our findings suggest that oral, intestinal, and pancreatic microbiomes are correlated and bacteria of oral origin exhibit co-abundance relationships and demonstrate complex correlation patterns in the intestinal and pancreatic tumor samples. Future prospective studies should aim to uncover the co-abundance of specific microbial communities for studying etiology of microbiota-driven carcinogenesis.

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Liver Fibrosis: Causes and Methods of Assessment, A Review

Romanian Journal Of Internal Medicine ◽

10.1515/rjim-2015-0039 ◽

2015 ◽

Vol 53 (4) ◽

pp. 304-314 ◽

Cited By ~ 6

Author(s):

Ali Erfani Karimzadeh Toosi

Keyword(s):

Liver Fibrosis ◽

Liver Biopsy ◽

Hepatic Dysfunction ◽

Current Knowledge ◽

Treatment Strategies ◽

Future Research ◽

Progressive Development ◽

Non Invasive ◽

The Past ◽

Invasive Method

AbstractHepatic fibrogenesis is the final result of injury to the liver. Fibrosis could lead to hepatic dysfunction, important in the pathogenesis of other chronic problems. Therefore, understanding the mechanism, accurate diagnosis and staging of it in early stages accelerates the treatment and reduces the prevalence of chirrosis. Treatment strategies of liver problems and detction methods depend on the amount and progression of liver fibrosis and the rate of cirrhosis development. Traditionally the invasive method, liver biopsy, is reference standard to follow progression and stage of fibrosis. However, during the past decade, progressive development of novel non-invasive methodologies has challenged the invasive method. Non-invasive methods have been initially introduced for chronic hepatitis C with increasing use in other chronic liver diseases. The need for liver biopsy has nowadays decreased significantly as a result of these methodologies. Most of the new non-invasive methods depend on either ‘biological’ or ‘physical’ approaches.In this review, starting from the mechanism of fibrogenesis, the current knowledge about diagnosis, treatment strategies and different methods for its evaluation is discussed. This is followed by a conclusion on what is expected to be known in this field during the future research.

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Oral Microbiota and Cancer Development

Pathobiology ◽

10.1159/000510979 ◽

2020 ◽

pp. 1-11 ◽

Cited By ~ 1

Author(s):

Heidi Tuominen ◽

Jaana Rautava

Keyword(s):

Oral Cavity ◽

Human Body ◽

Current Knowledge ◽

Fusobacterium Nucleatum ◽

Cancer Development ◽

Oral Microbiota ◽

Carcinogenic Potential ◽

Potentially Malignant ◽

Activate Cell ◽

The Impact

Oral microbiota are among the most diverse in the human body. More than 700 species have been identified in the mouth, and new sequencing methods are allowing us to discover even more species. The anatomy of the oral cavity is different from that of other body sites. The oral cavity has mucosal surfaces (the tongue, the buccal mucosa, the gingiva, and the palate), hard tissues (the teeth), and exocrine gland tissue (major and minor salivary glands), all of which present unique features for microbiota composition. The connection between oral microbiota and diseases of the human body has been under intensive research in the past years. Furthermore, oral microbiota have been associated with cancer development. Patients suffering from periodontitis, a common advanced gingival disease caused by bacterial dysbiosis, have a 2–5 times higher risk of acquiring any cancer compared to healthy individuals. Some oral taxa, especially <i>Porphyromonas gingivalis</i> and <i>Fusobacterium nucleatum</i>, have been shown to have carcinogenic potential by several different mechanisms. They can inhibit apoptosis, activate cell proliferation, promote cellular invasion, induce chronic inflammation, and directly produce carcinogens. These microbiota changes can already be seen with potentially malignant lesions of the oral cavity. The causal relationship between microbiota and cancer is complex. It is difficult to accurately study the impact of specific bacteria on carcinoma development in humans. This review focuses on the elucidating the interactions between oral cavity bacterial microbiota and cancer. We gather literature on the current knowledge of the bacterial contribution to cancer development and the mechanisms behind it.

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Inhibitory effects of different medicinal plants on growth of some oral microbiome member

Medycyna Weterynaryjna ◽

10.21521/mw.6433 ◽

2020 ◽

Vol 76 (08) ◽

pp. 6433-2020

Author(s):

Zoran Tambur ◽

Biljana Miljković-Selimović ◽

Dolores Opačić ◽

Ema Aleksić ◽

Luka Ivančajić ◽

...

Keyword(s):

Hypericum Perforatum ◽

Public Health Problem ◽

Fusobacterium Nucleatum ◽

Oral Microbiome ◽

Thymus Vulgaris ◽

Oral Microbiota ◽

Acorus Calamus ◽

Inhibitory Effects ◽

Oral Infections ◽

Ethanol Extracts

Oral infections and dental caries are still considered as a serious public health problem. Using the method of minimum inhibitory concentrations (MICs), the aim of this study was to investigate the inhibitory effects of 16 plants on the growth of Actinomyces odontolyticus, Streptococcus mitis, Streptococcus sanguinis, Eikenella corrodens, Fusobacterium nucleatum, Lactobacillus acidophilus and Streptococcus mutans. The most effective were ethanol extracts of Rosmarinus officinalis, Salvia officinalis, Thymus vulgaris, Calendula officinalis and Hypericum perforatum. The least efficiency was observed for Acorus calamus extract. Plant extracts could be used in oral health as therapeutic and prophylactic approach or in balancing oral microbiota.

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Malfunctional Reorganization in the Developing Limbo-Prefrontal System in Animals: Implications for Human Psychoses?

Zeitschrift für Neuropsychologie ◽

10.1024//1016-264x.12.1.8 ◽

2001 ◽

Vol 12 (1) ◽

pp. 8-14

Author(s):

Gertraud Teuchert-Noodt ◽

Ralf R. Dawirs

Keyword(s):

Prefrontal Cortex ◽

Mental Disorders ◽

Dentate Gyrus ◽

Cognitive Functions ◽

Experimental Approach ◽

Regulatory Mechanisms ◽

Hippocampal Dentate Gyrus ◽

Non Invasive ◽

Invasive Method ◽

Activity Dependent

Abstract: Neuroplasticity research in connection with mental disorders has recently bridged the gap between basic neurobiology and applied neuropsychology. A non-invasive method in the gerbil (Meriones unguiculus) - the restricted versus enriched breading and the systemically applied single methamphetamine dose - offers an experimental approach to investigate psychoses. Acts of intervening affirm an activity dependent malfunctional reorganization in the prefrontal cortex and in the hippocampal dentate gyrus and reveal the dopamine position as being critical for the disruption of interactions between the areas concerned. From the extent of plasticity effects the probability and risk of psycho-cognitive development may be derived. Advance may be expected from insights into regulatory mechanisms of neurogenesis in the hippocampal dentate gyrus which is obviously to meet the necessary requirements to promote psycho-cognitive functions/malfunctions via the limbo-prefrontal circuit.

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