OBJECTIVE:To investigate the distribution, lineage fate, and reparative function of Thy1 lineage cells in the mouse mandible. METHODS:Single-cell transcriptomic analysis was used to identify osteogenic subpopulations within mandibular mesenchymal stem cells. Lineage tracing in Thy1-CreERT2;Rosa26-tdTomato mice was employed to map the localization and osteogenic contribution of Thy1 lineage cells, while a critical-sized mandibular defect model was established to assess their reparative dynamics. Loss- and gain-of-function experiments were performed using Thy1-CreERT2;Rosa26-DTR mice and transplantation of purified tdTomato+ periosteal cells within hydrogel scaffolds. RESULTS:Single-cell analysis identified a Thy1-enriched osteoprogenitor subpopulation preferentially localized to the periosteum. Lineage tracing revealed that Thy1-lineage cells constituted a major proportion of periosteal osteogenic cells and exhibited clonogenic expansion and ectopic bone formation. Following mandibular injury, tdTomato+ cells progressively accumulated within the callus and represented the predominant osteogenic cell population at later stages. Genetic ablation of Thy1-lineage cells markedly impaired bone repair, whereas transplantation of purified tdTomato+ periosteal cells enhanced bone formation within the defect. CONCLUSIONS:Thy1 lineage periosteal cells represent a functionally important osteoprogenitor population in mandibular bone regeneration, providing a cellular framework for future mechanistic and translational studies.

[Objective:] To synthesize copper-composite mesoporous silica nanoparticles loaded with aminoguanidine (AG@Cu-MSNs) and investigate their effects on the osteogenic differentiation of methylglyoxal (MGO)-stimulated rat maxillary bone marrow stromal cells (M-BMSCs). [Methods:] Copper-composite mesoporous silica nanoparticles (Cu-MSNs) were prepared by the sol-gel method, and AG@Cu-MSNs were prepared by dispersing Cu-MSNs in deionized water containing aminoguanidine. The nanoparticles were characterized by scanning electron microscopy and transmission electron microscopy, and other techniques. M-BMSCs were cultured. The CCK-8 assay kit was used to determine the optimal stimulatory concentration of MGO on M-BMSCs and the co-culture concentration of composite nanoparticles with M-BMSCs. The live/dead staining assay was employed to assess the impact of composite nanoparticles on cell viability in MGO-stimulated conditions. After 7 days of mineralization induction, alkaline phosphatase (ALP) activity was assessed using an ALP assay kit. Real-time quantitative polymerase chain reaction (RT-qPCR) was used to detect the expression of some osteogenic related gene. Western blotting was used to detect the expression of osteogenesis-related proteins. [Results:] The application concentration of MGO was determined to be 0.5 mmol/L by CCK-8 assay. The results of CCK-8 assay and live/dead staining assay showed that the composite nanoparticles had good biocompatibility. Among them, the AG@Cu-MSNs group exhibited the highest cell viability and proliferation in MGO-stimulated conditions. After 7 days of mineralization induction, compared with the MGO stimulation group, the AG@Cu-MSNs group exhibited the most pronounced ALP staining intensity. Additionally, the expression levels of osteogenesis-related genes (Alpl, Runx2, Osx) and corresponding proteins (RUNX2, OSX) were significantly upregulated. [Conclusion:] In MGO-stimulated conditions, AG@Cu-MSNs significantly promotes the proliferation and osteogenic differentiation of M-BMSCs.

Cell membrane-coated nanoparticles (CMCNPs) are a class of nanoscale carriers enveloped by natural cell membranes, which efficiently preserve the abundant functional proteins and receptors on the surface of cell membranes, thereby integrating the biological properties of natural cell membranes and demonstrating good biocompatibility and targeting ability in the field of biomedicine. In treating various oral diseases such as oral cancer and periodontitis, CMCNPs have shown good potential and provided new research directions for overcoming related challenges in oral medicine, emerging as one of the forefront topics in current biomedical research. This paper focuses on CMCNPs and explores in depth the relevant mechanisms, application achievements, and existing challenges, aiming to provide a reference for the academic research and clinical translation of oral diseases such as oral cancer, periodontitis, and oral mucosal diseases.

The precise regulation of bone homeostasis and the balance between bone resorption and formation in periodontitis remain unclear. This study explores the role of long intergenic noncoding RNA-erythroid prosurvival (lincRNA-EPS) in inflammatory osteoclastogenesis and bone resorption. LincRNA-EPS knockout (KO) worsened LPS-induced alveolar bone resorption in vivo and osteoclast differentiation in vitro. Transcriptomics and protein sequencing showed dysregulated osteoclastogenesis and iron homeostasis without lincRNA-EPS, marked by increased expression of Lcn2. Knockdown of Lcn2 in osteoclast precursors (OCPs) resulted in a reduction in the level of iron metabolism and osteoclastogenesis; however, the regulatory response was delayed in KO cells. Correspondingly, overexpression of lincRNA-EPS accelerated the regulation of iron metabolism. Further, reducing Lcn2 levels in wildtype mice alleviated periodontitis-related bone loss, but not in KO mice. Taken together, we identified the critical role of lincRNA-EPS in regulating osteoclastogenesis under inflammatory environment, by preventing excessive iron metabolism caused by Lcn2.

Periodontitis, a multifactorial inflammatory disease driven by microbial dysbiosis, dysregulated immunity, and oxidative stress, demands therapeutic strategies that concurrently address interconnected pathological pathways. Here, a biomimetic lipid droplet-based nanoplatform (GA@LDs-CRAMP) is engineered to achieve spatiotemporal coordination of antibacterial, antioxidant, and immunomodulatory functions for the treatment of periodontitis. Constructed using RAW264.7 macrophage-derived lipid droplets (LDs), the GA@LDs-CRAMP system anchors cathelicidin-related antimicrobial peptide (CRAMP) onto LDs surfaces via lipopolysaccharide (LPS)-stimulated recruitment, while encapsulating gambogic acid (GA) within its hydrophobic core for mitochondria-targeted delivery. The nanoplatform demonstrates comprehensive therapeutic efficacy against periodontitis by suppressing periodontopathogen proliferation, restoring oxidative stress-damaged mitochondria through reactive oxygen species (ROS) scavenging, inhibiting inflammatory cascades via nuclear factor erythroid 2-related factor 2 (Nrf2) / nuclear factor-kappa B (NF-κB)-mediated antioxidant signaling activation, and reprogramming macrophage polarization from pro-inflammatory M1 to tissue-reparative M2 phenotypes. In preclinical periodontitis models, localized delivery of GA@LDs-CRAMP effectively mitigates inflammatory cytokine storms and attenuates alveolar bone resorption. Collectively, this study demonstrates the potential of leveraging lipid droplets organelles to engineer precision-targeted, multifunctional drug delivery systems for periodontitis therapy.

Osteoclasts are bone-resorbing cells that play essential roles in both physiological bone remodeling and pathological bone resorption. Inflammation serves as a significant inducer of pathological bone resorption. Studies have shown that osteoclasts differentiated in the inflammatory microenvironment originate from specific marked osteoclast precursors and also exhibit enhanced bone-resorbing capacity compared with those under physiological conditions. Moreover, these inflammation-derived osteoclasts further regulate bone destruction processes through crosstalk with stromal and immune cells. Therefore, osteoclasts in the inflammatory microenvironment are crucial for understanding the pathogenesis of inflammatory bone loss and developing targeted therapeutic strategies. This article reviews the differentiation mechanisms and functional properties of osteoclasts in the inflammatory microenvironment.

The complexity, high recurrence rate, and need for long-term monitoring in dermatophytosis treatment underscore the demand for high-performance antifungal strategies. Here, we present a theranostic wearable hydrogel dressing (LIG+ITZ@PCS hydrogel) that integrates laser-induced graphene (LIG) with co-encapsulated itraconazole (ITZ) for synergistic therapy and real-time monitoring. This platform features a cationic LIG+ surface (+43.1 mV) for targeted fungal capture. Sunlight exposure induces a mild photothermal effect (∼45°C), which enables the controlled release of ITZ. The combined action of photothermal therapy (PTT) and ITZ inflicts multimodal injury on Trichophyton rubrum (T. rubrum), inducing ferroptosis along with other cellular damage mechanisms. This mechanism achieves T. rubrum eradication and biofilm disruption without recurrence in murine models. The conductive LIG network facilitates real-time, smartphone-based tracking of fungal load through voltage signals. Furthermore, LIG+ITZ@PCS hydrogel exert a powerful modulates immune microenvironment effect. This intelligent system, which integrates low-temperature phototherapy, immunotherapy, and real-time sensing, offers a comprehensive platform for dermatophytosis management.

Mammalian lipid droplets (LDs), a class of cellular organelles associated with cellular metabolism, are composed of a neutral lipid core encapsulated by a monolayer phospholipid polar membrane. Initially regarded as static energy reservoirs with relatively simple functions, LDs have been the subject of recent advancements that have significantly expanded our understanding of their biogenesis mechanisms and functions. Beyond serving as central hubs for intracellular lipid metabolism, LDs actively participate in the pathogenesis and progression of inflammatory and infectious diseases, while playing critical regulatory roles in host immune responses. This paper provides a review of research in these fields.

In the original publication [...].

Aim or purpose: To clarify the contribution of Thy1+ cells to in situ osteogenesis in mandibular defect repair and define a new population of osteoprogenitor cells. Materials and methods: Mandibles from 10-week-old male C57BL/6 mice underwent scRNA-seq (GEO:GSM8311031). Thy1-CreER;tdTomato mice received intraperitoneal tamoxifen (1/3/8 weeks) for lineage tracing, with tdTomato+ cells tracked at 2d/1w via immunofluorescence. Critical-size mandibular defects (1.5mm) were generated, monitoring tdTomato+ cell recruitment at 1w/2w. Co-localization with Runx2+ osteoblasts was confirmed by dual staining. Thy1-CreER;DTR mice received diphtheria toxin (5μg/g) for Thy1+ cell ablation, and bone healing was assessed by micro-CT at 2 weeks. Statistical significance (p<0.05) was assessed by two-tailed t-tests. Results: scRNA-seq results showed that Thy1+ cells were concentrated in an independent osteoprogenitor cluster, and 54.17% of Thy1+ cells co-expressed Postn, a marker of periosteal cells. Lineage tracing revealed that Thy1+ cells were mainly located in the periosteum and all of them co-localized with osteoblasts. During the healing process of mandibular injury, Thy+ cells are activated and actively respond, and significantly accumulate in the injured area. Local ablation of Thy1+ cells significantly delayed the healing process of mandibular defects. Conclusions: Thy1+ skeletal stem cells are indispensable for craniofacial bone regeneration, with their spatiotemporal activation and osteogenic differentiation tightly coupled to defect microenvironmental cues. The anatomical localization and niche interaction patterns of these progenitors warrant further investigation to delineate their collaborative networks in bone repair.

Periodontitis, a chronic inflammatory disorder primarily induced by bacterial infection and exacerbated by excessive oxidative stress, leads to the destruction of alveolar bone. Diabetes mellitus intensifies this oxidative stress in periodontal tissues and disrupts the oral microbiome, thereby aggravating periodontal conditions and complicating the management of periodontitis. The development of materials that possess comprehensive therapeutic effects, including antibacterial, antioxidant, and osteogenic properties, for the treatment of diabetic periodontitis (DP) remains at the forefront of research. In this study, we introduced a copper hydrogen phosphate (CuHP) composite hydrogel, which exhibited multi-enzymatic activities at varying pH levels. This hydrogel was synthesized by encapsulating CuHP within a commercially available sodium alginate (SA) matrix. In vitro analyses explored the pH-responsive enzymatic activities, biocompatibility, and the antioxidant, osteogenic, and antibacterial properties of the resultant SA/CuHP composite hydrogel. At neutral pH, the hydrogel primarily exhibited catalase-like activity, providing it with antioxidant capabilities that reduced the inhibitory effects of oxidative stress on osteogenesis in bone marrow mesenchymal stem cells. In mildly acidic conditions, the hydrogel displayed peroxidase-like activity, catalysing the production of more potent reactive oxygen species and exhibiting significant antibacterial efficacy against Aggregatibacter actinomycetemcomitans. Furthermore, the SA/CuHP hydrogel continuously released copper ions, which synergistically enhance its osteogenic and antimicrobial efficacies. In vivo studies demonstrated that this composite hydrogel significantly inhibited bacterial growth and promoted bone regeneration in a rat model of DP. These findings suggest that the SA/CuHP hydrogel holds substantial potential for the treatment of periodontitis in patients with diabetes.

PURPOSE:The investigation into the capacity of PEEK material clasps to deliver sufficient retention force, maintain morphological stability, and exhibit fatigue resistance over prolonged periods is of significant importance. MATERIAL AND METHODS:This study employed a fatigue testing machine to simulate clinical scenarios with varying concave depths (0.25mm, 0.50mm, 0.75mm) and conducted 7200 cycles of fatigue tests on clasps made of different materials. The initial retention force, dynamic changes in retention force, and deformation values of the clasps were measured and analyzed, and their surface morphology was observed using Scanning Electron Microscopy (SEM). RESULTS:The initial retention force of A-type PEEK clasps exhibited an increase with the concave depth, whereas no significant difference was observed in the initial retention force of B-type PEEK clasps at different concave depths. Following fatigue cycling, the retention force of PEEK clasps decreased more gradually compared to metal clasps, with PEEK-A clasps demonstrating more stable retention force in deeper concave conditions. Furthermore, after prolonged fatigue cycles, PEEK clasps exhibited smaller permanent deformation than metal clasps, and their surface remained smoother without evident wear or cracks. CONCLUSIONS:In comparison to metal clasps, PEEK clasps offer more stable retention force and reduced permanent deformation in long-term clinical applications, making them more suitable for periodontal disease abutments with deeper concavity.

Aim or purpose: To investigate the role and underlying mechanism of long intergenic noncoding RNA-erythroid prosurvival (lincRNA-EPS) in inflammatory osteoclastogenesis. Materials and methods: Periodontitis was experimentally induced in 8-week-old male LincRNA-EPS-/- (KO) and wildtype (WT) C57BL/6 mice via lipopolysaccharide (LPS)-saturated silk ligature, following protocols approved by the Ethics Review Board of authors’ affiliation. After 14 days, alveolar bone resorption was quantified using micro-computed tomography. For in vitro osteoclastogenesis assays, bone marrow-derived macrophages (BMDMs) from both genotypes were stimulated with macrophage colony-stimulating factor, receptor activator for nuclear factor-κB ligand and LPS. Osteoclast formation was assessed through tartrate resistant acid phosphatase staining. Expression of osteoclast markers (Ctsk, Mmp9, Dcstamp, Nfatc1) was analyzed at mRNA and protein levels by real-time quantitative polymerase chain reaction (qPCR) and Western Blotting (WB). Transcriptomic profiling was conducted to identify the differentially expressed genes (DEGs) between WT and KO BMDMs during inflammatory osteoclast differentiation, and DEGs were verified through WB, immunofluorescence staining (IHC), qPCR, enzyme linked immunosorbent assay (ELISA). Results: LincRNA-EPS deletion exacerbated LPS-induced alveolar bone resorption in vivo and upregulated osteoclast markers in vitro. Transcriptomics revealed dysregulated iron metabolism, osteoclastogenesis, IL-17 signaling, and ferroptosis pathways, represented by up-regulated gene Lcn2. LCN2 upregulation and iron metabolism changes were confirmed via IHC, WB and ELISA. Conclusions: This study delineates the regulatory role of lincRNA-EPS in inflammation-driven osteoclastogenesis and reveals its mediation of iron-metabolism, which helps understanding pathology of and developing targeted therapy for inflammatory bone disorders.

Aim or purpose: This study engineers biomimetic lipid droplet-based nanotherapeutics that integrate antimicrobial and mitochondrial repair functions, overcoming the limitations of conventional periodontitis therapies in achieving simultaneous antibacterial, anti-inflammatory, and tissue-reparative effects. Materials and methods: In LPS-stimulated RAW264.7, CRAMP was recruited onto LDs, confirmed by IF and WB. GA loading efficiency (UV-Vis) and cytotoxicity (CCK-8) were assessed over 24–72 h. The diameter, zeta potential of GA@LDs-CRAMP were characterized via DLS. Bacterial inhibition against Aa and Pg was quantified via CFU. Mitochondrial repairing was validated using confocal (JC-1, MitoTracker) and DCFH-DA in MGFs. Inflammatory cytokines (IL-6, TNF-α, iNOS, Arg1) and Nrf2 pathway activation (RNA-seq) were quantified via qPCR in BMDMs. In vivo experiments employed 8-week-old male C57BL/6 mice (approved by the Ethics Committee). Periodontitis was induced by ligature placement for 14 days. Nanoparticles were administered locally every 3 days. Maxillae were analyzed by micro-CT and H&E, Masson staining. Inflammatory indicators were quantified via IHC. Statistical significance (p<0.05) was determined by ANOVA. Results: GA@LDs-CRAMP nanoparticles suppress periodontopathogens, repair mitochondria via ROS scavenging, inhibit inflammation through Nrf2 pathway activation, polarize macrophages to M2 phenotypes, and attenuate alveolar bone loss in murine periodontitis models. Conclusions: Bioengineered GA@LDs-CRAMP nanoparticles achieve multimodal periodontitis therapy through mitochondrial repair, anti-inflammatory action, and bone protection, leveraging endogenous lipid droplets to establish targeted nanomedicine and marking a breakthrough in precision treatment of inflammatory oral diseases.

Temporomandibular joint osteoarthritis (TMJOA) is a multifaceted degenerative disease characterized by progressive cartilage degradation, chronic pain, and functional limitations of the TMJ, significantly affecting patients’ quality of life. Although metabolic homeostasis in chondrocytes is crucial for cartilage health, the mechanisms underlying metabolic dysregulation in TMJOA remain poorly characterized. This study aimed to investigate the metabolic imbalance in TMJOA cartilage and explore novel therapeutic strategies targeting metabolic reprogramming. RNA sequencing revealed a significant imbalance between glycolysis and oxidative phosphorylation (OXPHOS) in TMJOA cartilage, with a marked shift toward glycolysis, which is associated with inflammation and cartilage degradation. To counteract this imbalance, Laccase domain-containing 1 (Lacc1), a metabolic regulator involved in both inflammation and metabolic homeostasis, was selected for investigation, as its role in chondrocytes had not been explored. We engineered macrophage-derived extracellular vesicles (EVs) to overexpress Lacc1 (OE-EVs), aiming to restore metabolic balance and modulate inflammation in chondrocytes. In vitro, OE-EVs significantly reduced IL-1β-induced inflammation, inhibited glycolysis by decreasing key glycolytic enzymes, improved mitochondrial function by decreasing mitochondrial superoxide levels, and the restoration of normal mitochondrial structure. In vivo, micro-computed tomography (Micro-CT) and histological analyses demonstrated that OE-EVs effectively alleviated inflammation and promoted cartilage repair, as indicated by a 1.55-fold increase in toluidine blue-stained cartilage area compared to the TMJOA group, reflecting improved cartilage matrix integrity and proteoglycan retention. These findings highlight the therapeutic potential of Lacc1-engineered EVs to target mitochondrial metabolism, reestablish metabolic homeostasis, and reduce inflammation in TMJOA, offering a novel and promising strategy for improving clinical outcomes in TMJOA patients.

Distinct clinical phenotypes of periodontitis are associated with specific microbiome profiles and diverse inflammatory conditions. Current drug delivery systems face challenges in precisely modulating this dynamic microenvironment. Effective inhibition of bone resorption can only be achieved through a strategic response to bacterial infections and inflammation within the periodontal pocket, followed by prompt treatment tailored to disease severity. In this study, tannic acid (TA) is loaded into hollow mesoporous silica nanoparticles (HMSNs) that are functionalized with positively charged polyarginines (R8) and negatively charged human serum albumin (HSA). These HMSNs-R8@TA-HSA (HRT) nanoparticles are then encapsulated within an injectable Nap-Gly-Phe-Phe-Tyr-OH (NapGFFY) hydrogel (NHRT). The intermediate linker R8 can interact with both arginine gingipain A (RgpA) and reactive oxygen species (ROS), which serve as markers of bacterial infections and inflammation, respectively. HSA, arginine, TA, and nitric oxide are differentially released from the hydrogel in response to varying concentrations of RgpA and ROS, demonstrating excellent antibacterial, antioxidant, and anti-inflammatory properties. This smart RgpA/ROS dual-responsive and injectable hydrogel with multifunctional therapy provides new prospects for the management of periodontitis.

Skin wound healing is often hindered by disrupted mitochondrial homeostasis and imbalanced macrophage glucose metabolism, posing a critical challenge to improve patient outcomes. Developing new wound healing dressings capable of effectively regulating macrophage immune-metabolic functions remains a pressing issue. Herein, a highly adhesive polyethylene glycol (PEG) hydrogel loaded with the Janus kinase 1 (JAK1) inhibitor Filgotinib (Fil@GEL) is prepared to modulate macrophage metabolic reprogramming and restore normal mitochondrial function. Fil@GEL exhibits superior shear adhesion strength compared to commercially available tissue binder products, providing adequate adhesion for skin wound closure. Additionally, Fil@GEL exhibits the capacity to inhibit M1-type macrophage polarization by suppressing the JAK-STAT signaling pathway, and induces a metabolic shift in macrophages from aerobic glycolysis to oxidative phosphorylation, which results in decreased lactate production, reduced reactive oxygen species (ROS) levels, and the restoration of mitochondrial homeostasis. The Fil@GEL hydrogel significantly accelerates skin wound healing compared to the control group, reduces intra-wound inflammation, and promotes collagen regeneration. In summary, this highly adhesive hydrogel demonstrates exceptional performance as a drug carrier, exerting immunometabolic modulation through firm wound adhesion and sustained filgotinib release, underscoring its substantial potential as an effective wound dressing.

PURPOSE:The use of postoperative radiotherapy (PORT) in patients with oral squamous cell carcinoma (OCSCC) lacks clear boundaries due to the non-negligible toxicity accompanying its remarkable cancer-killing effect. This study aims at validating the ability of deep learning models to develop individualized PORT recommendations for patients with OCSCC and quantifying the impact of patient characteristics on treatment selection. METHODS:Participants were categorized into two groups based on alignment between model-recommended and actual treatment regimens, with their overall survival compared. Inverse probability treatment weighting was used to reduce bias, and a mixed-effects multivariate linear regression illustrated how baseline characteristics influenced PORT selection. RESULTS:4990 patients with OCSCC met the inclusion criteria. Deep Survival regression with Mixture Effects (DSME) demonstrated the best performance among all the models and National Comprehensive Cancer Network guidelines. The efficacy of PORT is enhanced as the lymph node ratio (LNR) increases. Similar enhancements in efficacy are observed in patients with advanced age, large tumors, multiple positive lymph nodes, tongue involvement, and stage IVA. Early-stage (stage 0-II) OCSCC may safely omit PORT. CONCLUSIONS:This is the first study to incorporate LNR as a tumor character to make personalized recommendations for patients. DSME can effectively identify potential beneficiaries of PORT and provide quantifiable survival benefits.

The primary pathology of periodontitis involves the gradual deterioration of periodontal tissues resulting from the inflammatory reaction triggered by bacterial infection. In this study, a novel drug for periodontal pocket injection, known as the Shed-Cu-HA hydrogel, was developed by incorporating copper ions (Cu2+) and Shed-derived exosomes (Shed-exo) inside the hyaluronic acid (HA) hydrogel. Suitable concentrations of Cu2+ and Shed-exo released from Shed-Cu-HA enhanced cell viability and cell proliferation of human periodontal ligament stem cells. Additionally, the Shed-Cu-HA demonstrated remarkable antibacterial effects against the key periodontal pathogen (Aa) owing to the synergistic effect of Cu2+ and HA. Furthermore, the material effectively suppressed macrophage inflammatory response via the IL-6/JAK2/STAT3 pathway. Moreover, the Shed-Cu-HA, combining the inflammation-regulating properties of HA with the synergistic osteogenic activity of Shed-exo and Cu2+, effectively upregulated the expression of genes and proteins associated with osteogenic differentiation. The experimental findings from a mouse periodontitis model demonstrated that the administration of Shed-Cu-HA effectively reduced the extent of inflammatory cell infiltration and bacterial infections in gingival tissues and facilitated the regeneration of periodontal bone tissues and collagen after 2 and 4 weeks of injection. Consequently, it holds significant prospects for future applications in periodontitis treatment.