Dysbiosis in chronic periodontitis: Key microbial players and interactions with the human host

Abstract

Periodontitis is an extremely prevalent disease worldwide and is driven by complex dysbiotic microbiota. Here we analyzed the transcriptional activity of the periodontal pocket microbiota from all domains of life as well as the human host in health and chronic periodontitis. Bacteria showed strong enrichment of 18 KEGG functional modules in chronic periodontitis, including bacterial chemotaxis, flagellar assembly, type III secretion system, type III CRISPR-Cas system, and two component system proteins. Upregulation of these functions was driven by the red-complex pathogens and candidate pathogens, e.g. Filifactor alocis, Prevotella intermedia, Fretibacterium fastidiosum and Selenomonas sputigena. Nine virulence factors were strongly up-regulated, among them the arginine deiminase arcA from Porphyromonas gingivalis and Mycoplasma arginini. Viruses and archaea accounted for about 0.1% and 0.22% of total putative mRNA reads, respectively, and a protozoan, Entamoeba gingivalis, was highly enriched in periodontitis. Fourteen human transcripts were enriched in periodontitis, including a gene for a ferric iron binding protein, indicating competition with the microbiota for iron, and genes associated with cancer, namely nucleolar phosphoprotein B23, ankyrin-repeat domain 30B-like protein and beta-enolase. The data provide evidence on the level of gene expression in vivo for the potentially severe impact of the dysbiotic microbiota on human health.

Prevotella intermedia and periodontitis are associated with severe asthma

“…25 It is also a key factor in the triggering of periodontitis 26 and can stimulate the release of proinflammatory cytokines, proteinases, and matrix metalloproteinases (MMPs), which favor the development of periodontitis. The frequency of elevated levels of P. intermedia was greater in individuals with severe asthma as compared with those without this bronchial disease, suggesting that individuals with higher relative quantities of this bacterium are more likely to have severe asthma.…”

Plaque‐induced gingivitis: Case definition and diagnostic considerations

“…Emerging evidence suggests that clusters of bacteria, rather than individual species, might be of use as diagnostic markers for each disease; and that bacterial functions (e.g., proteolysis, flagellar assembly, bacterial motility) may be a more robust discriminant of disease than species. While these early novel findings support a gene‐centric rather than a species‐centric approach to disease causation, further studies are required to better characterize such bacterial clusters and gene functions and to validate their potential use both as a diagnostic tool and as response to treatment monitoring tool …”

Faecal freezing preservation period influences colonization ability for faecal microbiota transplantation

“…Key microbial players in gut microbiota are believed to trigger an inflammatory response via transition from the state of healthy symbiosis to dysbiosis (Belkaid and Hand 2014;Deng et al 2017). In turns, these events may induce a number of complex disorders, such as type II diabetes, rheumatoid arthritis, allergy, inflammatory bowel disease, periodontitis and even extreme obesity (Turnbaugh et al 2006;Scher and Abramson 2011;Liu et al 2012;Morgan et al 2012;Qin et al 2012;Smits et al 2013).…”