Gliding Rods

[This page is in progress.]

When seen in high numbers in the oral cavity, this cell morphology, typically representing Fusobacterium nucleatum or Capnocytophaga spp., does not necessarily denote pathogenicity. The destructive and inflammatory mechanisms of gliding rods are dependent not only on abundance, but species of bacteria they interact with in co-aggregations and biofilm adhesions. In adhesion forms, the bacterial pathogenicity may be amplified due to altered gene expression.¹

F. nucleatum can aid in transport when in close association with bacteria like Porphyromonas gingivalis, and it causes damage on its own as well.

“F. nucleatum is a potent stimulator of inflammatory cytokines, IL-6, IL-8, and TNFα. […] It is reported that F. nucleatum activates the immune responses through retinoic acid-inducible gene I (RIG-I). During periodontal health, the pro- and anti-inflammatory factors are maintained under homeostasis. Once disseminated outside the oral cavity and under dysbiosys, F. nucleatum induces exacerbated inflammation thus turning into a pathogen.”₂

“It has been demonstrated that F. nucleatum is invasive and pro-inflammatory in human oral epithelial cells, eliciting secretion of the pro-inflammatory chemokine IL-8.”

“The prevalence of F. nucleatum increases with the severity of disease, progression of inflammation and pocket depth…” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4323942/

“These observations are supported by animal studies in which a variety of cultivated and uncultivated oral species are found to co-translocate to the mouse placenta [54]. The majority of oral species translocated to the murine placenta were oral commensals, supporting the notion that commensals in the oral cavity may become pathogens elsewhere.”

Cardiovascular Disease

“Capnocytophaga, one of the genera of oral bacteria, has been implicated in the pathogenesis of several diseases, including endocarditis, septicaemia and disorders of the oral cavity such as abscesses and periodontal disease.”

Gastrointestinal Disorders

“By virtue of its adhesive and aggregative qualities, we suspected that F. nucleatum may be an overlooked member of the gut microbiota associated specifically with the mucosa and in this respect its invasive and pro-inflammatory characteristics might contribute to inflammatory bowel disease (IBD) etiology.”

“The association of F. nucleatum with IBD is intriguing in light of this pathogen’s well-characterized role in oral inflammatory diseases, given that there exists a potential link between IBD and periodontal disease (PD). The pathogenesis of PD and IBD share some key similarities. Both PD and IBD display hypersensitivity against commensal bacteria and much like in IBD, antibodies against various bacterial plaque components are present in the serum of patients with PD.”

“C. ochracea is also reported to be involved in several systemic diseases and to produce an immunosuppressive factor. C. ochracea has been implicated in focal infections, such as sepsis and purpura fulminans, and associations between high levels of antibodies to C. ochracea and coronary heart disease and a potential relationship with Sjögren’s syndrome have been reported.” Daichi Kita, et al. Involvement of the Type IX Secretion System in Capnocytophaga ochracea Gliding Motility and Biofilm Formation. Appl. Environ. Microbiol. March 2016 vol. 82 no. 6 1756-1766

Pregnancy Complications

“[F. nucleatum] has been recently shown to invade the amniotic membrane during pregnancy, leading to preterm labor and stillbirth.”

“Adverse pregnancy outcome (APO) is a broad term including preterm labor, chorioamnionitis, preterm premature rupture of membranes, preeclampsia, miscarriage, intrauterine growth retardation, low birth weight, stillbirth, neonatal sepsis, etc. F. nucleatum is one of the most prevalent species and by far the most prevalent oral species implicated in APO [30].”

“The prevalence of F. nucleatum detected in cord blood from neonatal sepsis equals or is higher than that of E. coli and Group B Streptococcus, placing F. nucleatum on the same importance scale as these two well-recognized neonatal pathogens [37]. These findings point to the urgent need to update the microbial diagnostic technologies employed by hospital laboratories.”

Other

F. nucleatum is also implicated in colorectal cancer:

“Oral and intestinal bacteria can alter the intestinal environment and in vivo studies aimed at determining the presence/absence of specific organisms under different host environments and dietary habits, as well as their cooccurrence with specific risk factors and biological markers (e.g., diabetes, obesity, smoking, alcohol, radiation therapy, adenomatous lesions), would likely provide novel insights into the microbiota-carcinoma relationship. […] Recent studies have detected a prevalence of oral fusobacteria (mainly F. nucleatum) in tissues from colorectal cancer patients and shown that strains isolated from inflamed biopsy tissue of intestinal disease patients display a more invasive phenotype (Strauss et al., 2011).”

“Despite the small number of patients included in this study, we were able to detect significantly more F. nucleatum and C. difficile in the Cancer Group patients compared to healthy controls, suggesting a possible role of these bacteria in colon carcinogenesis. This finding should be considered when screening for colorectal cancer.”

—

References

[1] Alfred B. Cunningham, et al. Bacteria in a Biofilm Have Different Characteristics than the Same Bacteria in Isolation. 2001-2010.

[2] Han YW. Fusobacterium nucleatum: a commensal-turned pathogen. Current opinion in microbiology. 2015;0:141-147. doi:10.1016/j.mib.2014.11.013.