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International Journal of Oral Science Apr 2020The human microbiome functions as an intricate and coordinated microbial network, residing throughout the mucosal surfaces of the skin, oral cavity, gastrointestinal... (Review)
Review
The human microbiome functions as an intricate and coordinated microbial network, residing throughout the mucosal surfaces of the skin, oral cavity, gastrointestinal tract, respiratory tract, and reproductive system. The oral microbiome encompasses a highly diverse microbiota, consisting of over 700 microorganisms, including bacteria, fungi, and viruses. As our understanding of the relationship between the oral microbiome and human health has evolved, we have identified a diverse array of oral and systemic diseases associated with this microbial community, including but not limited to caries, periodontal diseases, oral cancer, colorectal cancer, pancreatic cancer, and inflammatory bowel syndrome. The potential predictive relationship between the oral microbiota and these human diseases suggests that the oral cavity is an ideal site for disease diagnosis and development of rapid point-of-care tests. The oral cavity is easily accessible with a non-invasive collection of biological samples. We can envision a future where early life salivary diagnostic tools will be used to predict and prevent future disease via analyzing and shaping the infant's oral microbiome. In this review, we present evidence for the establishment of the oral microbiome during early childhood, the capability of using childhood oral microbiome to predict future oral and systemic diseases, and the limitations of the current evidence.
Topics: Child; Child Health; Humans; Infant; Microbiota; Mouth
PubMed: 32350240
DOI: 10.1038/s41368-020-0082-x -
Cancer Medicine Sep 2020Bacteria identified in the oral cavity are highly complicated. They include approximately 1000 species with a diverse variety of commensal microbes that play crucial... (Review)
Review
Bacteria identified in the oral cavity are highly complicated. They include approximately 1000 species with a diverse variety of commensal microbes that play crucial roles in the health status of individuals. Epidemiological studies related to molecular pathology have revealed that there is a close relationship between oral microbiota and tumor occurrence. Oral microbiota has attracted considerable attention for its role in in-situ or distant tumor progression. Anaerobic oral bacteria with potential pathogenic abilities, especially Fusobacterium nucleatum and Porphyromonas gingivalis, are well studied and have close relationships with various types of carcinomas. Some aerobic bacteria such as Parvimonas are also linked to tumorigenesis. Moreover, human papillomavirus, oral fungi, and parasites are closely associated with oropharyngeal carcinoma. Microbial dysbiosis, colonization, and translocation of oral microbiota are necessary for implementation of carcinogenic functions. Various underlying mechanisms of oral microbiota-induced carcinogenesis have been reported including excessive inflammatory reaction, immunosuppression of host, promotion of malignant transformation, antiapoptotic activity, and secretion of carcinogens. In this review, we have systemically described the impact of oral microbial abnormalities on carcinogenesis and the future directions in this field for bringing in new ideas for effective prevention of tumors.
Topics: Alphapapillomavirus; Bacteria, Aerobic; Bacteria, Anaerobic; Bacterial Translocation; Cell Transformation, Neoplastic; Disease Progression; Dysbiosis; Firmicutes; Fungi; Fusobacterium nucleatum; Humans; Immune Tolerance; Microbiota; Mouth; Neoplasms; Oropharyngeal Neoplasms; Porphyromonas gingivalis
PubMed: 32638533
DOI: 10.1002/cam4.3206 -
Periodontology 2000 Jun 2021Acquisition and establishment of the oral microbiota occur in a dynamic process over various stages and involve close and continuous interactions with the host and its... (Review)
Review
Acquisition and establishment of the oral microbiota occur in a dynamic process over various stages and involve close and continuous interactions with the host and its environment. In the present review, we discuss the stages of this process in chronological order. We start with the prenatal period and address the following questions: 'Is the fetus exposed to maternal microbiota during pregnancy?' and 'If so, what is the potential role of this exposure?' We comment on recent reports of finding bacterial DNA in placenta during pregnancies, and provide current views on the potential functions of prenatal microbial encounters. Next, we discuss the physiological adaptations that take place in the newborn during the birth process and the effect of this phase of life on the acquisition of the oral microbiota. Is it really just exposure to maternal vaginal microbes that results in the difference between vaginally and Cesarian section-born infants? Then, we review the postnatal phase, in which we focus on transmission of microbes, the intraoral niche specificity, the effects of the host behavior and environment, as well as the role of genetic background of the host on shaping the oral microbial ecosystem. We discuss the changes in oral microbiota during the transition from deciduous to permanent dentition and during puberty. We also address the finite knowledge on colonization of the oral cavity by microbes other than the bacterial component. Finally, we identify the main outstanding questions that limit our understanding of the acquisition and establishment of a healthy microbiome at an individual level.
Topics: Bacteria; Female; Humans; Infant, Newborn; Microbiota; Mouth; Pregnancy
PubMed: 33690935
DOI: 10.1111/prd.12366 -
International Journal of Molecular... Aug 2019The human organism coexists with its microbiota in a symbiotic relationship. These polymicrobial communities are involved in many crucial functions, such as immunity,... (Review)
Review
The human organism coexists with its microbiota in a symbiotic relationship. These polymicrobial communities are involved in many crucial functions, such as immunity, protection against pathogens, and metabolism of dietary compounds, thus maintaining homeostasis. The oral cavity and the colon, although distant anatomic regions, are both highly colonized by distinct microbiotas. However, studies indicate that oral bacteria are able to disseminate into the colon. This is mostly evident in conditions such as periodontitis, where specific bacteria, namely and project a pathogenic profile. In the colon these bacteria can alter the composition of the residual microbiota, in the context of complex biofilms, resulting in intestinal dysbiosis. This orally-driven disruption promotes aberrant immune and inflammatory responses, eventually leading to colorectal cancer (CRC) tumorigenesis. Understanding the exact mechanisms of these interactions will yield future opportunities regarding prevention and treatment of CRC.
Topics: Animals; Biodiversity; Colorectal Neoplasms; Disease Susceptibility; Dysbiosis; Gastrointestinal Microbiome; Host-Pathogen Interactions; Humans; Microbiota; Mouth
PubMed: 31450675
DOI: 10.3390/ijms20174146 -
Cells Aug 2019Salivary glands are essential structures in the oral cavity. A variety of diseases, such as cancer, autoimmune diseases, infections and physical traumas, can alter the... (Review)
Review
Salivary glands are essential structures in the oral cavity. A variety of diseases, such as cancer, autoimmune diseases, infections and physical traumas, can alter the functionality of these glands, greatly impacting the quality of life of patients. To date, no definitive therapeutic approach can compensate the impairment of salivary glands, and treatment are purely symptomatic. Understanding the cellular and molecular control of salivary glands function is, therefore, highly relevant for therapeutic purposes. In this review, we provide a starting platform for future studies in basic biology and clinical research, reporting classical ideas on salivary gland physiology and recently developed technology to guide regeneration, reconstruction and substitution of the functional organs.
Topics: Animals; Female; Gene Regulatory Networks; Humans; Male; Mice; Regeneration; Salivary Glands; Sex Characteristics; Species Specificity
PubMed: 31455013
DOI: 10.3390/cells8090976 -
International Journal of Molecular... Jul 2021The oral mucosa, which is the lining tissue of the oral cavity, is a gateway to the body and it offers first-line protection against potential pathogens, exogenous... (Review)
Review
The oral mucosa, which is the lining tissue of the oral cavity, is a gateway to the body and it offers first-line protection against potential pathogens, exogenous chemicals, airborne allergens, etc. by means of its physical and microbiological-immune barrier functions. For this reason, oral mucosa is considered as a mirror to the health of the individual as well as a guard or early warning system. It is organized in two main components: a physical barrier, which consists of stratified epithelial cells and cell-cell junctions, and a microbiological-immune barrier that keeps the internal environment in a condition of homeostasis. Different factors, including microorganism, saliva, proteins and immune components, have been considered to play a critical role in disruption of oral epithelial barrier. Altered mucosal structure and barrier functions results in oral pathologies as well as systemic diseases. About 700 kinds of microorganisms exist in the human mouth, constituting the oral microbiota, which plays a significant role on the induction, training and function of the host immune system. The immune system maintains the symbiotic relationship of the host with this microbiota. Crosstalk between the oral microbiota and immune system includes various interactions in homeostasis and disease. In this review, after reviewing briefly the physical barriers of oral mucosa, the fundamentals of oral microbiome and oral mucosal immunity in regard to their barrier properties will be addressed. Furthermore, their importance in development of new diagnostic, prophylactic and therapeutic strategies for certain diseases as well as in the application for personalized medicine will be discussed.
Topics: Animals; Homeostasis; Humans; Immunity, Mucosal; Microbiota; Mouth Mucosa
PubMed: 34360589
DOI: 10.3390/ijms22157821 -
Mucosal Immunology Nov 2021Oral mucosal disease (OMD), which is also called soft tissue oral disease, is described as a series of disorders or conditions affecting the mucosa and soft tissue in... (Review)
Review
Oral mucosal disease (OMD), which is also called soft tissue oral disease, is described as a series of disorders or conditions affecting the mucosa and soft tissue in the oral cavity. Its etiology is unclear, but emerging evidence has implicated the influence of the composition of the oral mucosa and saliva-resident microbiota. In turn, this dysbiosis effects the immune response balance and epithelial barrier function, followed by the occurrence and progression of OMD. In addition, oral microbial dysbiosis is diverse in different types of diseases and different disease progressions, suggesting that key causal pathogens may exist in various oral pathologies. This narrative literature review primarily discusses the most recent findings focusing on how microbial dysbiosis communicates with mucosal adaptive immune cells and the epithelial barrier in the context of five representative OMDs, including oral candidiasis (OC), oral lichen planus (OLP), recurrent aphthous ulcer (RAU), oral leukoplakia (OLK), and oral squamous cell carcinoma (OSCC), to provide new insight into the pathogenetic mechanisms of OMDs.
Topics: Animals; Biodiversity; Cell Communication; Disease Susceptibility; Dysbiosis; Homeostasis; Host Microbial Interactions; Host-Pathogen Interactions; Humans; Immune System; Immunity, Mucosal; Microbial Interactions; Microbiota; Mouth Mucosa; Signal Transduction
PubMed: 34040155
DOI: 10.1038/s41385-021-00413-7 -
International Journal of Molecular... Jul 2020Saliva is a highly versatile biological fluid that is easy to gather in a non-invasive manner-and the results of its analysis complement clinical and histopathological... (Review)
Review
Saliva is a highly versatile biological fluid that is easy to gather in a non-invasive manner-and the results of its analysis complement clinical and histopathological findings in the diagnosis of multiple diseases. The objective of this review was to offer an update on the contribution of salivary biomarkers to the diagnosis and prognosis of diseases of the oral cavity, including oral lichen planus, periodontitis, Sjögren's syndrome, oral leukoplakia, peri-implantitis, and medication-related osteonecrosis of the jaw. Salivary biomarkers such as interleukins, growth factors, enzymes, and other biomolecules have proven useful in the diagnosis and follow-up of these diseases, facilitating the early evaluation of malignization risk and the monitoring of disease progression and response to treatment. However, further studies are required to identify new biomarkers and verify their reported role in the diagnosis and/or prognosis of oral diseases.
Topics: Biomarkers; Humans; Intercellular Signaling Peptides and Proteins; Interleukins; Leukoplakia, Oral; Lichen Planus, Oral; Mouth; Osteonecrosis; Peri-Implantitis; Periodontitis; Saliva; Sjogren's Syndrome
PubMed: 32708341
DOI: 10.3390/ijms21145173 -
PloS One 2021Microorganisms in oral cavity are called oral microbiota, while microbiome consists of total genome content of microorganisms in a host. Interaction between host and... (Clinical Trial)
Clinical Trial
BACKGROUND
Microorganisms in oral cavity are called oral microbiota, while microbiome consists of total genome content of microorganisms in a host. Interaction between host and microorganisms is important in nervous system development and nervous diseases such as Autism, Alzheimer, Parkinson and Multiple Sclerosis (MS). Bacterial infections, as an environmental factor in MS pathogenesis play role in T helper 17(Th17) increase and it enhancing the production of pro-inflammatory cytokines such as Interlukin-21(IL-21), IL-17 and IL -22. Oral microbiota consists diverse populations of cultivable and uncultivable bacterial species. Denaturing gradient gel electrophoresis (DGGE) is an acceptable method for identification of uncultivable bacteria. In this study, we compared the bacterial population diversity in the oral cavity between MS and healthy people.
METHODS
From October to March 2019, samples were taken at Kermanshah University of Medical Sciences' MS patients center. A total of 30 samples were taken from MS patients and another 30 samples were taken from healthy people. Phenotypic tests were used to identify bacteria after pure cultures were obtained. DNA was extracted from 1 mL of saliva, and PCR products produced with primers were electrophoresed on polyacrylamide gels.
RESULTS
The genera Staphylococcus, Actinomyces, Fusobacterium, Bacteroides, Porphyromonas, Prevotella, Veillonella, Propionibacterium and uncultivable bacteria with accession number MW880919-25, JQ477416.1, KF074888.1 and several other un-culturable strains were significantly more abundant in the MS group while Lactobacillus and Peptostreptococcus were more prevalent in the normal healthy group according to logistic regression method.
CONCLUSION
Oral micro-organisms may alleviate or exacerbate inflammatory condition which impact MS disease pathogenesis. It may be assumed that controlling oral infections may result in reduction of MS disease progression.
Topics: Adult; Bacteria; Female; Humans; Mouth; Multiple Sclerosis
PubMed: 34847159
DOI: 10.1371/journal.pone.0260384 -
Medical Hypotheses Oct 2020There must be pathophysiological reason why "cold" viruses like SARS-CoV-2 show proclivity to nasal cavity, oral cavity, pharyngeal cavity and upper airways which have...
There must be pathophysiological reason why "cold" viruses like SARS-CoV-2 show proclivity to nasal cavity, oral cavity, pharyngeal cavity and upper airways which have lower temperature than core body temperature. Henceforth, facemasks' "therapeutic" role against SARS-CoV-2 must be explored because personal "therapeutic" environments may get created under facemasks due to rebreathing of ~95°F "hot" and ~80% "humid" exhalations which may constantly mitigate SARS-CoV-2 inside nasal cavity, oral cavity, pharyngeal cavity and upper airways.
Topics: Betacoronavirus; Body Temperature; COVID-19; Coronavirus Infections; Exhalation; Humans; Humidity; Masks; Mouth; Nasal Cavity; Pandemics; Pharynx; Pneumonia, Viral; SARS-CoV-2; Trachea
PubMed: 32460210
DOI: 10.1016/j.mehy.2020.109855