Subgingival Microbiota of Mexicans with Type 2 Diabetes with Different Periodontal and Metabolic Conditions

NOD2 contributes to Parvimonas micra-induced bone resorption in diabetic rats with experimental periodontitis

BACKGROUND

Type 2 diabetes mellitus (T2DM) may affect the oral microbial community, exacerbating periodontal inflammation; however, its pathogenic mechanisms remain unclear. As nucleotide-binding oligomerization domain 2 (NOD2) plays a crucial role in the activation during periodontitis (PD), it is hypothesized that changes in the oral microbial community due to diabetes enhance periodontal inflammation through the activation of NOD2.

METHODS

We collected subgingival plaque from 180 subjects who were categorized into two groups based on the presence or absence of T2DM. The composition of oral microbiota was detected by 16S rRNA high-throughput sequencing. In animal models of PD with or without T2DM, we assessed alveolar bone resorption by micro-computerized tomography and used immunohistochemistry to detect NOD2 expression in alveolar bone. Primary osteoblasts were cultured in osteogenic induction medium with high or normal glucose and treated with inactivated bacteria. After 24 h of inactivated bacteria intervention, the osteogenic differentiation ability was detected by alkaline phosphatase (ALP) staining, and the expressions of NOD2 and interleukin-12 (IL-6) were detected by western blot.

RESULTS

The relative abundance of Parvimonas and Filifactor in the T2DM group was increased compared to the group without T2DM. In animal models, alveolar bone mass was decreased in PD, particularly in T2DM with PD (DMPD) group, compared to controls. Immunohistochemistry revealed NOD2 in osteoblasts from the alveolar bone in both the PD group and DMPD group, especially in the DMPD group. In vitro, intervention with inactivated Parvimonas significantly reduced ALP secretion of primary osteoblasts in high glucose medium, accompanied by increased expression of NOD2 and IL-6.

CONCLUSIONS

The results suggest that T2DM leading to PD may be associated with the activation of NOD2 by Parvimonas.

Analysis of subgingival microbiota and IL-1β, TNF-α and CX3CL1 levels in gingival crevicular fluid of fixed dental prostheses

Prosthetic biomaterials can affect the composition of the subgingival microbiota and consequently the production of proinflammatory cytokines, causing damage to the periodontium. A total of 40 patients were divided into two groups: 20 with monolithic zirconia (MZ) prostheses and 20 with porcelain fused to metal (PFM) with nickel-chromium (Ni-Cr) alloy prostheses. Subgingival plaque and gingival crevicular fluid samples were taken. The Checkerboard technique for DNA-DNA hybridization and the enzyme-linked immunosorbent assay technique were performed. Teeth with MZ presented a lower percentage of bleeding on probing and tooth mobility compared to teeth with PFM with Ni-Cr alloy. Prosthodontic teeth harbored higher total levels of the 18 bacterial species than non-prosthodontic teeth. There was a higher prevalence of S. gordonii and V. parvula species in PFM with Ni-Cr alloy compared to MZ. There was an increase in IL-1β, TNF-α and CX3CL1 levels in PFM with Ni-Cr alloy compared to MZ. MZ is a candidate biomaterial with fewer negative effects on the periodontium, allowing for longer prostheses longevity in the mouth.

Effect of adjuvant probiotic therapy (Lactobacillus reuteri) in the treatment of periodontitis associated with diabetes mellitus: clinical, controlled, and randomized study

OBJECTIVES

Subgingival instrumentation (SI) with probiotics may be a proposal for the treatment of periodontitis (P), for patients with type 2 diabetes mellitus (T2DM). The Lactobacillus reuteri probiotic as an adjunctive therapy in the treatment of P associated with T2DM was evaluated.

MATERIALS AND METHODS

Forty diabetic participants diagnosed with P (stage III and IV, grade B) were randomized into SI + Placebo (n = 20): subgingival instrumentation plus placebo lozenges and SI + Probi (n = 20): subgingival instrumentation plus probiotics. Probing depth (PD), gingival recession (GR), clinical attachment level (CAL), plaque index (PI), bleeding on probing (BoP), and PISA index were performed at baseline and 30, 90, and 180 days. Cytokine concentration in the gingival crevicular fluid, subgingival biofilm sample, and LDL and HDL subfractions were evaluated.

RESULTS

In the deep pockets, PD in SI + Probi showed increased values (p = 0.02) compared to SI + Placebo at 90 days. For CAL, SI + Probi showed increased values compared to SI + Placebo, with a significant difference at 30 days (p = 0.03), 90 days (p = 0.02), and 180 days (p = 0.04). At #PD ≥ 7 mm, SI + Probi had a more frequent number of sites (p = 0.03) compared to SI + Placebo only at baseline. For the PISA, SI + Probi showed a significant difference (p = 0.04) compared to SI + Placebo at 90 days. For cytokines, SI + Probi showed higher quantification than SI + Placebo for IL-10 (p < 0.001) at 90 days, IL-12 (p = 0.010) at 90 days, IL-1β (p = 0.035) at 90 days, and IL-8 (p = 0.003) at baseline. SI + Placebo showed higher quantification of IL-1β (p = 0.041) compared to SI + Probi only at 30 days. There was a reduction in all microbial complexes. SI + Probi improved LDL size (246.7 nm vs 260.4 nm; p < 0.001), while large HDL subfractions were reduced aft 180 days of treatment (24.0% vs 20.3%; p = 0.022) when compared with SI + Placebo; this response was dependent of probiotics (1.0 mg/dL vs - 6.2 mg/dL; p = 0.002).

CONCLUSION

Subgingival instrumentation improved the clinical periodontal parameters in patients with T2DM. The use of L. reuteri probiotics had no additional effects compared with the placebo; however, there was a positive effect on the lipoprotein subfraction.

CLINICAL RELEVANCE

Scientific rationale for study: subgingival instrumentation with probiotics may be a proposal for the treatment of periodontitis (P), especially for patients with type 2 diabetes mellitus (T2DM).

PRINCIPAL FINDINGS

the use of L. reuteri probiotics had no additional effects compared with the placebo; however, there was a positive effect on the lipoprotein subfraction.  Practical implications: L. reuteri as an adjunct to subgingival instrumentation may have significant therapeutic implications in dyslipidemia.

Patients with type 2 diabetes and severe periodontitis harbor a less pathogenic subgingival biofilm than normoglycemic individuals with severe periodontitis

BACKGROUND

Whether, and to what extent, diabetes mellitus (DM) can affect the subgingival biofilm composition remains controversial. Thus, the aim of this study was to compare the composition of the subgingival microbiota of non-diabetic and type 2 diabetic patients with periodontitis using 40 "biomarker bacterial species."

METHODS

Biofilm samples of shallow (probing depth [PD] and clinical attachment level [CAL] ≤3 mm without bleeding) and deep sites (PD and CAL ≥5 mm with bleeding) of patients with or without type 2 DM were evaluated for levels/proportions of 40 bacterial species by checkerboard DNA-DNA hybridization.

RESULTS

A total of 828 subgingival biofilm samples from 207 patients with periodontitis (118 normoglycemic and 89 with type 2 DM) were analyzed. The levels of most of the bacterial species evaluated were reduced in the diabetic compared with the normoglycemic group, both in shallow and in deep sites. The shallow and deep sites of patients with type 2 DM presented higher proportions of Actinomyces species, purple and green complexes, and lower proportions of red complex pathogens than those of normoglycemic patients (P < 0.05).

CONCLUSIONS

Patients with type 2 DM have a less dysbiotic subgingival microbial profile than normoglycemic patients, including lower levels/proportions of pathogens and higher levels/proportions of host-compatible species. Thus, type 2 diabetic patients seem to require less remarkable changes in biofilm composition than non-diabetic patients to develop the same pattern of periodontitis.

Probiotic Monotherapy with Lactobacillus reuteri (Prodentis) as a Coadjutant to Reduce Subgingival Dysbiosis in a Patient with Periodontitis

(1) Background: Probiotics can be considered a non-invasive periodontal monotherapy for the modulation of microbiota when periodontal treatment is not accessible. The aim was to evaluate the ability of Lactobacillus reuteri Prodentis as monotherapy to modulate periodontal parameters and subgingival biofilm dysbiosis. (2) Methods: A 30-year-old patient with periodontitis was followed longitudinally after one month of daily consumption of L. reuteri Prodentis (T0). Periodontal measurements and microbial identification by Checkerboard DNA−DNA hybridization of 40 bacteria were compared between baseline (T0) and 30 days (T1) or 90 days (T2), using the Kruskal−Wallis (KW) and Mann−Whitney U (MW) tests. (3) Results: Low values of pocket depth, attachment level, dental plaque, gingival erythema (GE), and suppuration were observed at T0 vs. T1, with the clinical improvement of GE (p < 0.05, MW) and the recovery of tooth 46 fistulation. T1 vs. T0 comparisons showed lower levels (Lev) or proportions (Prop) of Parvimonas micra (Lev: p < 0.05, MW; Prop: p < 0.01, MW) and Streptococcus gordonii (Prop: p < 0.05, MW), and a predominance (Lev/Prop) of Actinomyces odontolyticus and Streptococcus mitis; lower levels and proportions of P. micra, Eubacterium saburreum, Porphyromonas gingivalis, and Tannerella forsythia were observed in tooth 46 (T1/T2 vs. T0). (4) Conclusions: Under monotherapy with L. reuteri Prodentis, periodontal measurements of the patient were maintained, with selective changes in the subgingival microbiota that were proportional to the time of probiotic administration, with any additional periodontal treatment.

Association between metabolic syndrome and periodontitis: The role of lipids, inflammatory cytokines, altered host response, and the microbiome

Periodontitis has been associated with many systemic diseases and conditions, including metabolic syndrome. Metabolic syndrome is a cluster of conditions that occur concomitantly and together they increase the risk of cardiovascular disease and double the risk of type 2 diabetes. In this review, we focus on the association between metabolic syndrome and periodontitis; however, we also include information on diabetes mellitus and cardiovascular disease, since these two conditions are significantly intertwined with metabolic syndrome. With regard to periodontitis and metabolic syndrome, to date, the vast majority of studies point to an association between these two conditions and also demonstrate that periodontitis can contribute to the development of, or can worsen, metabolic syndrome. Evaluating the effect of metabolic syndrome on the salivary microbiome, data presented herein support the hypothesis that the salivary bacterial profile is altered in metabolic syndrome patients compared with healthy patients. Considering periodontitis and these three conditions, the vast majority of human and animal studies point to an association between periodontitis and metabolic syndrome, diabetes, and cardiovascular disease. Moreover, there is evidence to suggest that metabolic syndrome and diabetes can alter the oral microbiome. However, more studies are needed to fully understand the influence these conditions have on each other.

Screening for prevalence and abundance of Capnocytophaga spp by analyzing NGS data: A scoping review

BACKGROUND

Capnocytophaga spp. are commensal bacteria of the oral cavity and constitute a genus of the core microbiome.

OBJECTIVE

This genus is responsible for many local and systemic conditions in both the immunocompetent and immunocompromised patients, but its beneficial or deleterious role in the microbiota has been little explored.

DESIGN

Online databases were used to identify papers published from 1999 to 2019 based on next-generation sequencing (NGS) data to study comparative trials. Work using other identification methods, case reports, reviews, and non-comparative clinical trials was excluded.

RESULTS AND CONCLUSION

We selected 42 papers from among 668 publications. They showed a link between the abundance of Capnocytophaga spp. in the oral microbiota and various local pathologies (higher for gingivitis and halitosis; lower in active smokers, etc.) or systemic diseases (higher for cancer and carcinomas, IgA nephropathy, etc.). After discussing the limits inherent to the NGS techniques, we present several technical and biological hypotheses to explain the diversity of results observed between studies, as well as the links between the higher or lower abundance of Capnocytophaga spp and the appearance of local or systemic conditions and diseases.

Diabetes and Oral Health: Summary of Current Scientific Evidence for Why Transdisciplinary Collaboration Is Needed

This Perspective provides a brief summary of the scientific evidence for the often two-way links between hyperglycemia, including manifest diabetes mellitus (DM), and oral health. It delivers in a nutshell examples of current scientific evidence for the following oral manifestations of hyperglycemia, along with any available evidence for effect in the opposite direction: periodontal diseases, caries/periapical periodontitis, tooth loss, peri-implantitis, dry mouth (xerostomia/hyposalivation), dysbiosis in the oral microbiome, candidiasis, taste disturbances, burning mouth syndrome, cancer, traumatic ulcers, infections of oral wounds, delayed wound healing, melanin pigmentation, fissured tongue, benign migratory glossitis (geographic tongue), temporomandibular disorders, and osteonecrosis of the jaw. Evidence for effects on quality of life will also be reported. This condensed overview delivers the rationale and sets the stage for the urgent need for delivery of oral and general health care in patient-centered transdisciplinary collaboration for early detection and management of both hyperglycemia and oral diseases to improve quality of life.

Glycated hemoglobin influence on periodontal status, pathogens and salivary interleukins in type II diabetic Tunisian subjects with chronic periodontitis

BACKGROUND/PURPOSE

Studies have shown that there is a possible correlation between the amount of glycated hemoglobin and the periodontal status. The goal of this study was to investigate the relationship between glycated hemoglobin (HbA1c) and the prevalence of gingival pathogens and circulating interleukin levels in type II diabetic Tunisian subjects.

MATERIAL AND METHODS

The research included four groups; 30 healthy subjects (H group), 30 non-diabetic subjects suffering from chronic periodontitis (CP group). Type-II diabetic patients were divided according to HbA1c level into 30 adequately-controlled type-II diabetes subjects (HbA1c ≤ 7 percent (ATIID&CP group)) and 30 inadequately-controlled type-II diabetes subjects and HbA1c > 7 percent (ITIID&CP group). Clinical periodontal condition parameters and assessment of salivary interleukin IL-1beta, IL-6 and IL-10 were assessed. Quantitative Polymerase Chain Reaction used for detection of Subgingival biofilm of periodontal pathogens.

RESULTS

Clinical parameters analyzed were positively associated with HbA1c levels (p < 0.05). A. Actinomycetemcomitans were found in 80 percent of ITIID&CP, 65 percent of CP and almost absent in H group. Porphyromonas gingivalis was present in 100 percent of CP, 85 percent of ITIID&CP, 50 percent of ATIID&CP and 3 percent of H group. T. Denticola had an equivalent occurrence. While Tannerella forsythia was scarce in ITIID&CP groups, but abundant in the H group. ITIID&CP had the highest IL-6 and IL-1beta/IL-10 ratios.

CONCLUSION

HBA1c levels affect periodontal status, pathogens and salivary interleukins in Type-II diabetic Tunisians with chronic periodontitis, compared with stable and chronic periodontitis groups and can interact with periodontal infections and increase the inflammatory state.

Impact of Diabetes on the Gut and Salivary IgA Microbiomes

Mucosal surfaces like those present in the lung, gut, and mouth interface with distinct external environments. These mucosal gateways are not only portals of entry for potential pathogens but also homes to microbial communities that impact host health. Secretory immunoglobulin A (SIgA) is the single most abundant acquired immune component secreted onto mucosal surfaces and, via the process of immune exclusion, shapes the architecture of these microbiomes. Not all microorganisms at mucosal surfaces are targeted by SIgA; therefore, a better understanding of the SIgA-coated fraction may identify the microbial constituents that stimulate host immune responses in the context of health and disease. Chronic diseases like type 2 diabetes are associated with altered microbial communities (dysbiosis) that in turn affect immune-mediated homeostasis. 16S rRNA gene sequencing of SIgA-coated/uncoated bacteria (IgA-Biome) was conducted on stool and saliva samples of normoglycemic participants and individuals with prediabetes or diabetes (n = 8/group). These analyses demonstrated shifts in relative abundance in the IgA-Biome profiles between normoglycemic, prediabetic, or diabetic samples distinct from that of the overall microbiome. Differences in IgA-Biome alpha diversity were apparent for both stool and saliva, while overarching bacterial community differences (beta diversity) were also observed in saliva. These data suggest that IgA-Biome analyses can be used to identify novel microbial signatures associated with diabetes and support the need for further studies exploring these communities. Ultimately, an understanding of the IgA-Biome may promote the development of novel strategies to restructure the microbiome as a means of preventing or treating diseases associated with dysbiosis at mucosal surfaces.

Two Bariatric Surgical Procedures Differentially Alter the Intestinal Microbiota in Obesity Patients

AIMS

To explore the intestinal microbiota composition affected by the two most widely used procedures of bariatric surgery, laparoscopic sleeve gastrectomy (LSG) and laparoscopic roux-en-Y gastric bypass (LRYGB), in Chinese obesity patients.

METHODS

Stool samples were collected from the obese patients before (n = 87) and with follow-up after the surgery (n = 53). After DNA extraction, 16S rDNA (V3 + V4 regions) sequencing was completed on Illumina HiSeq 2500 sequencing platform. The samples were analyzed base on four groups, pre-LSG (n = 54), pre-LRYGB (n = 33), post-LSG (n = 33), and post-LRYGB (n = 20). The linear mixed models were used to analyze the alteration of intestinal microbiota before and after the surgeries of LSG or LRYGB. Student's t test and χ2 test were used for analysis of independent groups; Metastats analysis was used to compare the relative abundance of bacteria, and Pearson correlation and Spearman correlation analysis were used to test the correlation between indicated groups.

RESULTS

87 patients were included and 53 (60.92%) of them completed the follow-up (9.60 ± 3.92 months). Body mass index (BMI) decreased from 37.84 ± 6.16 kg/m2 to 26.22 ± 4.33 kg/m2 after LSG and from 45.75 ± 14.26 kg/m2 to 33.15 ± 10.99 kg/m2 after LRYGB. The relative abundance of 5 phyla and 42 genera were altered after the surgery in the cohort. Although no alteration of Firmicutes was observed at phylum level, 54.76% of the altered genera belong to phylum Firmicutes. Both LSG and LRYGB procedures increased the richness and evenness of intestinal microbiota in obese patients after the surgery. Particularly, 33 genera altered after LSG and 19 genera altered after LRYGB, in which 11 genera were common alterations in both procedures.

CONCLUSION

Both LSG and LRYGB altered the composition of intestinal microbiota in Chinese obesity patients, and particularly increased the richness and evenness of microbiota. Genera belonging to phylum Firmicutes were the most altered bacteria by bariatric surgery. The procedure of LSG resulted in much more pronounced alteration of the intestinal microbiota abundance than that observed in LRYGB. While different genera were altered after LSG and LRYGB procedures, 10 genera were the common altered genera in both procedures. Bacteria altered after LSG and LRYGB were functionally associated with BMI, and with relieving of the metabolic syndromes.