A novel lncRNA-mediated epigenetic regulatory mechanism in periodontitis

LncRNA HOTTIP as a potential biomarker of chronic periodontitis and its role in inflammatory responses

Chronic periodontitis (CP) is a prevalent oral condition that can elicit a broad spectrum of inflammatory responses. This study investigates the impact of lncRNA HOTTIP on inflammatory responses of CP via targeting and regulating miR-205-5p. This study involved 117 CP patients and 101 controls. The expression levels of HOTTIP and miR-101-3p in the gingival crevicular fluid (GCF) of CP patients were quantified using qPCR. The levels of inflammatory factors IL-1β, IL-6, IL-10, and TNF-α, were measured through ELISA. ROC analysis was conducted to evaluate the diagnostic efficacy. The LPS-induced hPDLFs injury model was established to investigate the effects of HOTTIP silencing, as well as the concurrent inhibition of HOTTIP and miR-101-3p expression, on cellular functionality and inflammatory responses. HOTTIP was elevated in the GCF of CP patients, whereas miR-101-3p was reduced (P < 0.001). HOTTIP exhibited a positive correlation with inflammatory markers and periodontal indicators (r > 0, P < 0.01). HOTTIP possessed the potential to serve a specific biomarker for the auxiliary diagnosis of CP (AUC = 0.967, P < 0.001), as well as a critical parameter for assessing the periodontal condition of patients. In LPS-induced hPDLFs model, the silencing of HOTTIP was found to enhance cell proliferation (P < 0.01), reduce apoptosis (P < 0.001), and the release of inflammatory factors (P < 0.05). However, the simultaneous inhibition of both HOTTIP and miR-101-3p, this inhibitory effect on inflammatory response was counteracted (P < 0.05). HOTTIP regulated cellular function and the release of inflammatory factors via miR-101-3p, thereby exacerbating the inflammatory response with CP patients. HOTTIP is anticipated to emerge as a promising biomarker for the diagnosis of CP.

m6A-Modified GATA2 Enhances Odontogenic Differentiation in Stem Cells from the Apical Papilla

Epigenetic modifications play a crucial role in regulating stem cell differentiation. Among these, N6-methyladenosine (m6A) modification significantly impacts mRNA stability and translation. However, its role in dental stem cell differentiation remains largely unexplored. Functional assays, including ALP activity, alizarin red S staining, qPCR, and Western blot, were conducted to assess odontogenic differentiation. Then, an in vivo dentin formation model was used to validate our findings. Additionally, we employed RNA stability assays and m6A site mutagenesis to investigate the regulatory mechanism of m6A modification in GATA2-mediated differentiation. Our results demonstrated that overexpression of GATA2 significantly promoted SCAP odontogenic differentiation. Moreover, in vivo studies confirmed that GATA2 overexpression enhances dentin formation in mouse models. Conversely, knockdown of GATA2 or mutation of its m6A sites led to reduced mRNA stability and decreased odontogenic differentiation. m6A modification is enriched in the 3' untranslated region (3'UTR) of GATA2 mRNA, regulating its stability and expression. Our findings indicate that m6A modification contributes to the post-transcriptional regulation of GATA2, enhancing its stability and promoting SCAP-mediated odontogenic differentiation and dentin formation. This study provides new insights into the epigenetic regulation of dental stem cells and suggests a potential molecular target for dental tissue regeneration.

Application of Single-Cell Genomics to Animal Models of Periodontitis and Peri-Implantitis

AIMS

This narrative review aims to synthesize current knowledge on integrating single-cell genomics technologies with animal models of periodontitis and peri-implantitis.

REVIEW

Single-cell RNA sequencing (scRNAseq) reveals cellular heterogeneity and specific cell roles in periodontitis and peri-implantitis, overcoming the limitations of bulk RNA sequencing. Under controlled conditions and genetic manipulation, animal models facilitate studying disease progression, gene functions and systemic disease links, aiding targeted therapy development. Knockout models have started to elucidate the impact of genetic mutations on periodontal disease and host responses. scRNAseq in animal models has been used to examine connections between periodontitis and systemic diseases, revealing altered immune environments and cellular interactions. Emerging studies are now applying these methods to animal models of peri-implantitis. Integrating these datasets into single-cell and spatially resolved atlases will enable future meta-analyses, providing deeper insights into disease mechanisms considering factors such as sex, strain, and age.

CONCLUSIONS

Integrating scRNAseq with animal models advances the understanding of periodontitis and peri-implantitis pathogenesis and precision therapies. The combined use of single-cell and spatial genomics and scRNAseq will further enhance data insights significantly for drug discovery and preclinical testing, making these technologies pivotal in validating animal models and translating findings into clinical practice.

Emerging therapeutic strategies targeting bone signaling pathways in periodontitis

Periodontitis is a multifactorial immune-mediated disease exacerbated by dysregulated alveolar bone homeostasis. Timely intervention is crucial for disease management to prevent tooth loss. To successfully manage periodontitis, it is imperative to understand the cellular and molecular mechanisms involved in its pathogenesis to develop novel treatment modalities. Non-surgical periodontal therapy (NSPT) such as subgingival instrumentation/debridement has been the underlying treatment strategy over the past decades. However, new NSPT approaches that target key signaling pathways regulating alveolar bone homeostasis have shown positive clinical outcomes. This narrative review aims to discuss endogenous bone homeostasis mechanisms impaired in periodontitis and highlight the clinical outcomes of preventive periodontal therapy to avoid invasive periodontal therapies. Although the anti-resorptive therapeutic adjuncts have demonstrated beneficial outcomes, adverse events have been reported. Diverse immunomodulatory therapies targeting the osteoblast/osteoclast (OB/OC) axis have shown promising outcomes in vivo. Future controlled randomized clinical trials (RCT) would help clinicians and patients in the selection of novel preventing therapies targeting key molecules to effectively treat or prevent periodontitis.

Recent Advance in Single-Molecule Fluorescent Biosensors for Tumor Biomarker Detection

The construction of biosensors for specific, sensitive, and rapid detection of tumor biomarkers significantly contributes to biomedical research and early cancer diagnosis. However, conventional assays often involve large sample consumption and poor sensitivity, limiting their further application in real samples. In recent years, single-molecule biosensing has emerged as a robust tool for detecting and characterizing biomarkers due to its unique advantages including simplicity, low sample consumption, ultra-high sensitivity, and rapid assay time. This review summarizes the recent advances in the construction of single-molecule biosensors for the measurement of various tumor biomarkers, including DNAs, DNA modifications, RNAs, and enzymes. We give a comprehensive review about the working principles and practical applications of these single-molecule biosensors. Additionally, we discuss the challenges and limitations of current single-molecule biosensors, and highlight the future directions.

Highlights on the Effects of Non-Coding RNAs in the Osteonecrosis of the Jaw

Osteonecrosis of the jaw is the progressive loss and destruction of bone affecting the maxilla or mandible in patients treated with antiresorptive and antiangiogenic agents without receiving prior radiation therapy. The pathogenesis involves the inflammatory pathway of receptor activator of nuclear factor NF-kB ligand and the macrophage colony-stimulating factor, essential for osteoclast precursors survival and proliferation and acting through its receptor c-Fms. Evidence has shown the role of non-coding RNAs in the pathogenesis of osteonecrosis of the jaw and this finding might be useful in diagnosis since these small RNAs could be considered as biomarkers of apoptotic activity in bone. Interestingly, it has been proved that miR-29 and miR-31-5p, acting on specific targets such as CALCR and RhoA, promote programmed-cell death and consequently the necrosis of bone tissue. Specific long non-coding RNAs, instead, have been detected both at reduced levels in patients with multiple myeloma and osteonecrosis, and associated with suppression of osteoblast differentiation, with consequences in the progression of mandible lesions. Among non-coding genic material, circular RNAs have the capability to modify the expression of specific mRNAs responsible for the inhibition of bisphosphonates activity on osteoclastogenesis.