Dark field microscopy of the subgingival microflora in insulin-dependent diabetics

The association between Type 1 diabetes mellitus and periodontal diseases

BACKGROUND/PURPOSE

Type 1 diabetes mellitus (T1DM) is a chronic autoimmune disease affecting oral health. Evidence shows possible association between T1DM and periodontal diseases (PDs). We conducted a nationwide population-based study in Taiwan, with a 14-year follow-up to investigate the risk of PDs in T1DM patients.

METHODS

We used data from the National Health Insurance Research Database in Taiwan. The T1DM cohort was identified with newly diagnosed T1DM from 1998 to 2011. The non-T1DM cohort was frequency matched with the T1DM cohort. Participants comprised 4248 patients in the T1DM cohort and 16992 persons in the non-T1DM cohort.

RESULTS

The T1DM patients showed an increased risk of PDs compared to non-T1DM individuals [adjusted hazard ratio (aHR) = 1.45]. T1DM patients who visited the emergency room more than twice per year had a higher aHR of 13.0 for developing PDs. The aHR for PDs was 13.2 in the T1DM patients who had been hospitalized more than twice per year.

CONCLUSION

T1DM patients are at higher risk of developing PDs than non-T1DM individuals. Our results further showed that the number of T1DM interventions; that is, annual emergency visits and hospitalizations were associated with increased the risk of developing PDs.

Common mechanisms involved in Alzheimer's disease and type 2 diabetes: a key role of chronic bacterial infection and inflammation

Strong epidemiologic evidence and common molecular mechanisms support an association between Alzheimer's disease (AD) and type 2-diabetes. Local inflammation and amyloidosis occur in both diseases and are associated with periodontitis and various infectious agents. This article reviews the evidence for the presence of local inflammation and bacteria in type 2 diabetes and discusses host pathogen interactions in chronic inflammatory disorders. Chlamydophyla pneumoniae, Helicobacter pylori and spirochetes are demonstrated in association with dementia and brain lesions in AD and islet lesions in type 2 diabetes. The presence of pathogens in host tissues activates immune responses through Toll-like receptor signaling pathways. Evasion of pathogens from complement-mediated attack results in persistent infection, inflammation and amyloidosis. Amyloid beta and the pancreatic amyloid called amylin bind to lipid bilayers and produce Ca(2+) influx and bacteriolysis. Similarly to AD, accumulation of amylin deposits in type 2 diabetes may result from an innate immune response to chronic bacterial infections, which are known to be associated with amyloidosis. Further research based on an infectious origin of both AD and type 2 diabetes may lead to novel treatment strategies.

Microbiological changes after periodontal therapy in diabetic patients with inadequate metabolic control

The present study investigated the effect of non-surgical periodontal treatment (SRP) on the composition of the subgingival microbiota of chronic periodontitis (CP) in individuals with type 2 diabetes (DM2) with inadequate metabolic control and in systemically healthy (SH) individuals. Forty individuals (20 DM2 and 20 SH) with CP underwent full-mouth periodontal examination. Subgingival plaque was sampled from 4 deep sites of each individual and tested for mean prevalence and counts of 45 bacterial taxa by the checkerboard method. Clinical and microbiological assessments were performed before and 3 months after SRP. At baseline, those in the DM2 group presented a significantly higher percentage of sites with visible plaque and bleeding on probing compared with those in the SH group (p<0.01). Those in the DM2 group presented significantly higher levels of C. rectus and P. gingivalis, and lower prevalence of P. micra and S. anginosus, compared with those in the SH group (p≤0.001). At the 3-month visit, both groups showed a significant improvement in all clinical parameters (p<0.01). Those in the DM2 group showed significantly higher prevalence and/or levels of A. gerencseriae, A. naeslundii I, A. oris, A. odontolyticus, C. sputigena, F. periodonticum, and G. morbillorum compared with those in the SH group (p≤0.001). However, those in the DM2 group showed a significant reduction in the levels of P. intermedia, P. gingivalis, T. forsythia, and T. denticola (p≤0.001) over time. Those in the SRP group showed improved periodontal status and reduced levels of putative periodontal pathogens at 3 months' evaluation compared with those in the DM2 group with inadequate metabolic control.

Emerging roles of pathogens in Alzheimer disease

Chronic spirochetal infection can cause slowly progressive dementia, cortical atrophy and amyloid deposition in the atrophic form of general paresis. There is a significant association between Alzheimer disease (AD) and various types of spirochete (including the periodontal pathogen Treponemas and Borrelia burgdorferi), and other pathogens such as Chlamydophyla pneumoniae and herpes simplex virus type-1 (HSV-1). Exposure of mammalian neuronal and glial cells and organotypic cultures to spirochetes reproduces the biological and pathological hallmarks of AD. Senile-plaque-like beta amyloid (Aβ) deposits are also observed in mice following inhalation of C. pneumoniae in vivo, and Aβ accumulation and phosphorylation of tau is induced in neurons by HSV-1 in vitro and in vivo. Specific bacterial ligands, and bacterial and viral DNA and RNA all increase the expression of proinflammatory molecules, which activates the innate and adaptive immune systems. Evasion of pathogens from destruction by the host immune reactions leads to persistent infection, chronic inflammation, neuronal destruction and Aβ deposition. Aβ has been shown to be a pore-forming antimicrobial peptide, indicating that Aβ accumulation might be a response to infection. Global attention and action is needed to support this emerging field of research because dementia might be prevented by combined antibiotic, antiviral and anti-inflammatory therapy.

Collagenases in gingival crevicular fluid in type 1 diabetes mellitus

BACKGROUND

Studies have demonstrated that high levels of collagenase activity in gingival crevicular fluid (GCF) are associated with degradation of periodontal tissues in progressive periodontitis compared to periodontally healthy tissues. Because the activation of collagenases is an important issue in periodontitis, we have studied the activation of collagenase in gingival crevicular fluid samples of diabetic patients.

METHODS

Collagenase activity was studied in human gingival crevicular fluids. Twenty-two poorly controlled diabetic patients (e.g., blood glucose: 11.0+/-0.7 mmol/l; hemoglobin A1c [HbA1c]: 9.6%+/-0.3%) and five well-controlled diabetic patients were compared to six chronic periodontitis subjects and five healthy controls. Collagenase activity against type I collagen was measured using sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis quantitated by laser densitometry.

RESULTS

The poorly controlled diabetic patients had more alveolar bone loss than the well-controlled diabetic subjects and controls (P<0.001; t test). The activity of collagenases in GCF in poorly controlled diabetic patients was similar to that seen in chronic periodontitis subjects (P>0.05) but higher than in healthy controls (P<0.01; t test), whereas there was no difference between the well-controlled diabetic subjects and systemically healthy controls (P>0.05; t test).

CONCLUSION

Poorly controlled diabetes is strongly related to periodontal tissue destruction, and collagenases in GCF may mediate and reflect this effect.

[Gastrointestinal complications of diabetes mellitus]

BACKGROUND

Diabetes mellitus leads to a broad spectrum of symptoms and manifestations in the field of gastroenterology.

BASIS

This article reviews the pathophysiology, differential diagnoses and secondary diseases of the gastrointestinal tract in diabetic patients.

CLINICAL APPEARANCE

Motility disorders, infectious complications, secondary diseases of the stomach, liver, pancreas, gall bladder, small and large bowel are considered and discussed. Diagnostic and therapeutic approaches for the management of diabetic enteropathy are presented.

CONCLUSION

The new strategies in diagnosis and therapy for a successful prevention or treatment of gastrointestinal complications due to diabetes mellitus need good cooperation of clinical specialties.