Only the SNP rs6667202 was associated with AgP in a Brazilian population, being the minor C allele protective against AgP. Moreover, SNPs rs1333048 and rs1537415, previously associated with AgP in other population, was not validated to Brazilian population.

Aim: To compare the salivary proteomic profile of periodontitis-affected (PA) parents and their offspring to periodontally healthy (PH) dyads in the pursuit of possible biomarkers for early diagnosis of this disease.Materials and Methods: Unstimulated saliva samples collected from 17 pairs of PA or PH individuals and their children were submitted to mass spectrometric analyses followed by proteomic analyses. Primary PA fibroblasts were triggered towards having an inflammatory response, and an immunoenzymatic assay of its supernatant was performed to validate the obtained data.Results: ANXA1, KRT4, GSTP1, HPX, A2M and KRT13 were lower in PA parents and their children, and IGHG1, CSTB, KRT9, SMR3B, IGHG4 and SERPINA1 were higher.ANXA1 presented the highest fold change, 7.1 times less produced in children of PA parents, and was selected as a potential biomarker for periodontitis. The in vitro assay also showed lower ANXA1 production by cells of PA patients. Conclusion:Before any clinical sign of periodontal loss, descendants of PA patients have an altered proteomic profile compared to PH individuals, presenting a lower abundance of ANXA1. This protein is suggested as a potential biomarker for periodontitis.

Background and objective:Previous studies have demonstrated an association between the IL10 promoter rs6667202 (C > A) single-nucleotide polymorphism (SNP) and grade C, stage 3 or 4 periodontitis (Perio4C) in the Brazilian population, where the altered A allele was detected more frequently in these patients. However, no functional analysis of this variation has yet been performed. Thus, the objective of this preliminary study was to evaluate the functionality of rs6667202 in gingival fibroblasts (GFs) of individuals with Perio4C and with periodontal health (PH) stimulated with Aggregatibacter actinomycetencomitans protein extract (AaPE).Methods: Patients with PH and Perio4C were segregated according to their genotype (AA, AC, or CC), and a biopsy was performed to establish the culture of the GFs.After GFs exposure to AaPE at 5 µg/ml for 1.5 h, RNA was extracted to analyze IL10 expression by qPCR. Aliquots of the cell's supernatant were subjected to immunoenzymatic analysis (MAGpix) to detect interleukin-10 (IL-10). Results:In PH, the genotypes AA and AC are related to less expression of IL10 (p = 0.027 and p < 0.0001) and less production of IL-10 (p = 0.002 and p = 0.001), when compared to CC. In Perio4C, there was no statistical difference between the genotypes (p > 0.05), although a lower IL-10 expression and release compared with PH CC was seen (p = 0.033 and p < 0.001). Conclusion:The rs6667202 SNP is functional in PH, as it decreases the expression and production of IL-10. In Perio4C, other factors may be masking its action by altering the IL-10's response.

Background In Grade C periodontitis in young patients (PerioC‐Y), the functional roles of the subgingival community after years of periodontal treatment are still underexplored. This study evaluated the taxonomic and predicted functional content of the subgingival microbiome of PerioC‐Y patients under supportive periodontal therapy (SPT). Methods Clinical and microbiological data from subgingival biofilm were assessed from 10 PerioC‐Y patients at two time points: at baseline and after 5.7 ± 1.3 years of SPT. This was compared with 15 patients without a history of periodontitis. The V1‐V3 and V4‐V5 regions of the 16S rRNA were sequenced using the Illumina Miseq. Microbial composition was evaluated by the core microbiome, and alpha‐ and beta‐diversity. The microbiome functional content was predicted using Picrust2, and the gene differential abundance was analyzed with DESeq2. Results Clinical improvements were seen in PerioC‐Y‐SPT. Differences in β‐diversity between PerioC‐Y and health were observed (health x PerioC‐Y‐baseline, P = 0.02; health x PerioC‐Y‐SPT, P = 0.05). Moreover, although β‐diversity did not statistically change between baseline and SPT in PerioC‐Y, the microbial correlation evidenced increased Streptococcus and decreased Treponema network contributions during SPT. Based on predicted functional data, treatment induced a reduction in genes related to flagellar protein and signal transduction in PerioC‐Y. However, compared with healthy individuals, some genes remained more highly abundant in PerioC‐Y‐SPT, such as quorum sensing and efflux pump transporters. Conclusion Despite clinical improvements and a shift in taxonomic composition, the PerioC‐Y patients' periodontal treatment was not enough to reach a similar microbiome to patients without disease experience. Some functional content in this biofilm remained altered in PerioC‐Y regardless of disease control.

Grade C periodontitis in youngers is characterized by a severe form of periodontitis, and IL10 rs6667202 single nucleotide polymorphism (SNP) has been described as an important feature in this disease etiology. Aim: This study aimed to evaluate, in vivo, the functionality of IL10 rs6667202 SNP on IL-10 gingival fluid levels. Methods: Thirty patients with Perio4C were selected, 15 with the IL10 AA genotype (rs6667202) and 15 with AC/CC genotypes. The gingival fluid was collected from two sites with probing depth ≥ 7 mm and bleeding on probing, and two healthy sites. The IL-10 concentration was determined by Luminex/MAGpix platform. Results: In deep pockets, the IL10 AA genotype presented a lower concentration of IL-10 when compared with AC or CC genotypes (p<0.05). In shallow pockets, no difference between groups was seen (p>0.05). Conclusion: IL10 rs6667202 SNP decreases the production of IL-10 in crevicular fluid, potentially affecting this disease progression.