Journal of periodontal research最新文献

Aim: Porphyromonas gingivalis lipopolysaccharide (PgLPS) is a significant virulence factor and a driver of early innate immune responses in epithelial cells. The presence of PgLPS in immediate proximity to gingival epithelium induces significant inflammatory responses. In primary human gingival keratinocytes (HGK), we utilized transcriptome analysis to elucidate the change in early gene expression induced by PgLPS.

Methods: HGK cell cultures were treated with PgLPS (4 h), and RNA was extracted and prepared for RNA sequence (RNAseq) analysis. Differentially expressed genes (DEGs) were identified, and potential interactions between these genes were subsequently examined using gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analytic approaches to identify significantly enriched pathways. Expression of genes associated with relevant pathways was evaluated using real-time quantitative reverse-transcription polymerase chain reaction (RT-qPCR).

Results: RNAseq analysis identified 25 DEGs, and GO and KEGG analytic approaches showed related genes expressed in two general pathways. First, pathways broadly related to urokinase and coagulation included the genes PLAU, PLAUR, and SerpinB2. In RT-qPCR analysis, these genes were induced by PgLPS over time (4-24 h), and these data were consistent with PgLPS induction of cell migration. Second, interleukin-1 (IL-1) receptor binding and cytokine-activity pathways were also enriched. Genes associated with these pathways included IL36G, IL1B, IL1RN, and CXCL14. RT-qPCR analysis confirmed PgLPS induction of genes associated with the IL-1family. When expression of IL1B and IL36G genes was examined in relation to their respective antagonists, only IL36G gene expression was increased. CXCL14 gene expression was reduced over time, and this was consistent with RNAseq analysis.

Conclusions: Genes associated with significantly enriched GO and KEGG pathways are relevant to aspects of periodontal disease (PDD) pathogenesis. First, PgLPS induced expression of PLAU, PLAUR, and SerpinB2, and these changes were consistent with an increase in cell migration that was found. Second, both IL36G and IL1B gene expression was significantly induced, but only IL36G in relation to its selective antagonist (IL36RN) was increased. These data support that early upregulation of IL36G may serve as an alarmin that can drive early innate immune inflammatory responses in HGK. Further in vivo testing of these findings is ongoing.

Aims: Orthodontic force (OF) induces a variety of reactions in the periodontal ligament (PDL) that could potentially account for individual variability regarding orthodontic tooth movement (OTM). This study investigates the transcriptomic profile of human PDL tissue subjected to OF in vivo for 7 and 28 days, additionally comparing the differences between maxillary and mandibular PDL.

Methods: Healthy patients requiring orthodontic premolar extractions were randomly assigned to one of three groups: control (CG) where no OF was applied, 7 days and 28 days, where premolars were extracted either 7 or 28 days after the application of a 50-100 g OF. Total RNA was extracted from the PDL tissue and analyzed via RNA-seq. Differentially expressed genes (DEGs) were identified using a false discovery rate and fold change threshold of < 0.05 and ≥ 1.5 respectively. Functional and Protein-Protein Interaction analysis were performed.

Results: After 7 days of OF, the reaction of PDL to OF is characterized by cell responses to stress, increased bone resorption, inflammation and immune response, and decreased bone formation. In contrast, after 28 days, bone regeneration is more prominent, and processes of bone homeostasis, immune response, and cell migration are present. The response of maxillary and mandibular PDL was different. Bone resorption was observed in the maxilla at 7 and 28 days, while in the mandible expression of cell proliferation and transcriptional activity were predominant after 28 days of OF.

Conclusions: The early reaction of the PDL to OF corresponds with increased bone resorption and decreased bone formation. After 28 days, bone formation became more prominent. The maxillary and mandibular PDL present asynchronous responses during OTM. These findings enhance our comprehension of the mechanisms underlying the origin-specific responses of PDL to different lengths of OF, which is potentially relevant in the development of personalized therapeutic strategies.

Flowchart and timeline (in hours) of the in vitro experimental procedures.

Aim: This study investigated the activity and mechanism of action of the iron tetracarboxyphthalocyanine (FeTcPc) on tumor necrosis factor alpha (TNF-α) production and its impact on experimental periodontitis.

Methods: RAW 264.7 macrophages were treated with FeTcPc, activated with lipopolysaccharide (LPS) at 10 ng/mL, and the TNF-α levels were measured, as well as the nuclear factor kappa B (NF-κB) activation. Subsequently, a mouth gel containing 1% FeTcPc was topically administered to the gingival tissue of mice with periodontitis-induced ligatures. Bone loss and the gene expression of Tnfα, p65 (NF-κB), and receptor-activating nuclear factor kappa B ligand (Rankl) were quantified in gingival tissue. Finally, the systemic toxicity of FeTcPc was estimated in Galleria mellonella larvae.

Results: In an activated RAW 264.7 macrophage culture, 100 μM FeTcPc reduced TNF-α release and NF-κB activation. Regarding experimental periodontitis, topical application of mouth gel containing 1% FeTcPc blocked alveolar bone loss. Additionally, 1% FeTcPc reduced the expression of Tnfα, p65 (NF-κB), and Rankl in gingival tissue. Finally, administration FeTcPc at doses ranging from 1 to 1000 mg/kg did not cause acute systemic toxicity in G. mellonella.

Conclusion: Overall, we demonstrated the potential of mouth gel containing FeTcPc as a therapeutic strategy for managing osteolytic inflammatory disorders, such as periodontitis.

Aim: We investigated the in vitro effect of Limosilactobacillus reuteri DSM 17938 supernatant on the inflammatory response of human gingival fibroblasts (HGF) challenged by lipopolysaccharide (LPS) or elevated glucose levels.

Methods: HGF were exposed to LPS (1 μg/mL), glucose (5, 12 mM or 25 mM), and dilutions of supernatant prepared from L. reuteri DSM 17938 (0.5 × 10⁷, 1.0 × 10⁷, 2.5 × 10⁷, and 5.0 × 10⁷ CFU/mL). After 24 h cell viability and levels of cytokines (IL-1β, IL-6 and IL-8) and TLR-2 were determined.

Results: None of the tested L. reuteri (DSM 17938) supernatant concentrations reduced the viability of HGF. Supernatant concentrations (2.5 × 10⁷ and 5 × 10⁷ CFU/mL) significantly (p < .05) decreased the production of IL-1β, IL-6, IL-8, and TLR-2 in the presence of LPS. In contrast, inflammatory markers were not reduced by L. reuteri supernatant in the presence of glucose. Glucose concentrations of 12 mM and 24 mM still lead to an elevated production of the investigated biochemical mediators.

Conclusion: While L. reuteri (DSM 17938) supernatant attenuates the inflammatory response of HGF to LPS in a dose-dependent manner, elevated glucose levels suppress this action. These in vitro results support the overall anti-inflammatory efficacy of L. reuteri supplementation in plaque-associated periodontal inflammations.

Studies examining the link between periodontitis and survival outcomes have yielded conflicting results in patients with chronic kidney disease (CKD). This systematic review with meta-analysis aims to assess the association between periodontitis and cardiovascular or all-cause mortality in CKD patients. A thorough search was conducted on the PubMed, Web of Science, and Embase databases for studies investigating the association between periodontitis and survival outcomes in CKD patients. Two authors independently scanned the titles or abstracts and then identified the eligible full-text article based on the PECOS criteria: Participants (CKD patients), Exposure (periodontitis), Comparison (mild/no periodontitis), Outcomes (cardiovascular or all-cause mortality), and Study design (retrospective or prospective cohort). Six cohort studies, including 7731 patients, were identified. The included studies had low-to-moderate risk of bias. The mean/median follow-up duration ranged from 18.1 months to 8.67 years. The all-cause mortality rate was 44.8% for patients with periodontitis and 28.0% for controls. Meta-analysis showed that periodontitis, defined through clinical attachment loss (CAL), was significantly associated with an increased risk of all-cause (adjusted hazard ratio [HR] 1.24; 95% confidence intervals [CI] 0.89-1.72; I² = 80.9%) and cardiovascular mortality (HR 1.57; 95% CI 1.08-2.27; I² = 34.0%). Additionally, a significant association between periodontitis and the risk of cardiovascular or all-cause mortality was observed in studies with a predominance of females, follow-up duration ≥5 years, all stages of CKD, and low risk of bias subgroups. Periodontitis is significantly associated with an increased risk of all-cause and cardiovascular mortality in CKD patients within low risk of bias subgroup or based on defining periodontitis through CAL. Registration number: PROSPERO CRD42018512391.

Various mechanical loadings, including mechanical stress, orthodontics forces, and masticatory force, affect the functions of periodontal ligament cells. Regulation of periodontal tissue destruction, formation, and differentiation functions are crucial processes for periodontal regeneration therapy. Numerous studies have reported that different types of mechanical loading play a role in maintaining periodontal tissue matrix homeostasis, and osteogenic differentiation of the periodontal ligament cells. This scoping review aims to evaluate the studies regarding the effects of various mechanical loadings on the secretion of extracellular matrix (ECM) components, regulation of the balance between formation and destruction of periodontal tissue matrix, osteogenic differentiation, and multiple differentiation functions of the periodontal ligament. An electronic search for this review has been conducted on two databases; MEDLINE via PubMed and SCOPUS. Study selection criteria included original research written in English that reported the effects of different mechanical loadings on matrix homeostasis and differentiation potential of periodontal ligament cells. The final 204 articles were mainly included in the present scoping review. Mechanical forces of the appropriate magnitude, duration, and pattern have a positive influence on the secretion of ECM components such as collagen, as well as regulate the secretion of matrix metalloproteinases and tissue inhibitors of matrix metalloproteinases. Additionally, these forces regulate a balance between osteoblastic and osteoclast differentiation. Conversely, incorrect mechanical loadings can lead to abnormal formation and destruction of both soft and hard tissue. This review provides additional insight into how mechanical loadings impact ECM homeostasis and multiple differentiation functions of periodontal ligament cells (PDLCs), thus making it valuable for regenerative periodontal treatment. In combination with advancing technologies, the utilization of ECM components, application of different aspects of mechanical force, and differentiation potential of PDLCs could bring potential benefits to future periodontal regeneration therapy.

Aims: This study aimed to elucidate the alterations in Follistatin-like protein 1 (FSTL1) and its association with the pathological process of periodontitis.

Methods: This study included 48 patients with periodontitis and 42 healthy controls. The expression level of FSTL1 in the gingiva was determined by RT-qPCR, validated using the dataset GSE16134, and subsequently examined by western blotting. Bioinformatics analysis revealed a single-cell distribution of FSTL1, characteristic of angiogenesis and immune cell infiltration. The expression and distribution of FSTL1, vascular endothelial marker protein CD31 and myeloperoxidase (MPO), the indicator of neutrophil activity, were determined by immunohistochemistry (IHC). A series of correlation analyses was performed to determine the associations between FSTL1 and clinical parameters, including probing depth (PD) and clinical attachment loss (CAL), and their potential role in angiogenesis (CD31) and neutrophil infiltration (MPO).

Results: FSTL1 was significantly upregulated in the gingiva of patients with periodontitis compared to their healthy counterparts. In addition, FSTL1 was positively correlated with the clinical parameters PD (r = .5971, p = .0005) and CAL (r = .6078, p = .0004). Bioinformatic analysis and IHC indicated that high FSTL1 expression was significantly correlated with angiogenesis and neutrophil infiltration in periodontitis. Moreover, receiver operating characteristic (ROC) analysis demonstrated that FSTL1 could serve as an independent indicator for evaluating the severity of periodontitis (area under the curve [AUC] = 0.9011, p < .0001).

Conclusion: This study demonstrated FSTL1 upregulation in periodontitis and its potential contribution to the disease via angiogenesis and neutrophil infiltration.