Caspase-3 and gasdermin E mediate macrophage pyroptosis in periodontitis.

BACKGROUND AND OBJECTIVES: Periodontitis is a chronic inflammatory disease linked to pyroptosis, an inflammatory cell death process. Macrophages are essential for maintaining microenvironment homeostasis, which is crucial for periodontal health. This study explores the mechanisms underlying the relationship between macrophage pyroptosis and periodontitis. METHODS: Expression of the pyroptosis marker gasdermin E (GSDME) and the macrophage surface marker CD68 was examined by immunofluorescence double staining in healthy and periodontitis gingival tissues. In an in vitro pyroptosis model, RAW264.7 cells were irritated using Porphyromonas gingivalis-lipopolysaccharide (P. gingivalis-LPS) after treatment with either a nuclear factor kappa-B (NF-κB) agonist or inhibitor. The mRNA and protein levels of NF-κB, caspase-3, GSDME, and interleukin-1ß (IL-1ß) were evaluated through qRT-PCR, western blotting, and ELISA techniques. RESULTS: GSDME and CD68 were heavily elevated in inflamed gingival tissues compared to healthy tissues and co-localized in the same region. Furthermore, exposure to P. gingivalis-LPS resulted in a significant upregulation of NF-κB, caspase-3, GSDME, and IL-1ß at both the mRNA and protein levels in RAW264.7 cells. NF-κB agonist or inhibitor pretreatment enhanced or inhibited these effects. CONCLUSIONS: GSDME-mediated macrophage pyroptosis is implicated in periodontitis. Based on in vitro experiments, P. gingivalis-LPS causes pyroptosis in RAW264.7 cells through the caspase-3/GSDME pathway. Furthermore, NF-κB regulates this pyroptotic pathway.

Copper-deposited diatom-biosilica enhanced osteogenic potential in periodontal ligament stem cells and rat cranium.

This study aimed to establish that copper-deposited Diatom-biosilica have the potential and possibility for clinical applications in repairing bone defects in a state of inflammation, such as periodontitis. Treatment of alveolar bone defects caused by periodontitis is a major challenge for clinicians. To achieve better repair results, the material should not only be bone conductive but also have the ability to stimulate osteogenesis and angiogenesis at the lesion site. Copper (II) and silicon (IV) ions could react to form basic copper silicate, which promoted both osteogenesis and angiogenesis. The mineralized diatom (Cu-DBs) loaded with copper (II) ions were synthesized by processing diatom shells using a hydrothermal method. Periodontal ligament stem cells (PDLSCs) are used to detect the osteogenic properties of Cu-DBs at the gene and protein levels. Using a rat cranial defect model and a full-thickness skin incision model to test the osteogenic properties of Cu-DBs in vivo. Compared with untreated diatoms (DBs), Cu-DBs extract significantly promoted the expression of osteogenesis-related factors like ALP, RUNX2, BSP, OCN, and OPN in PDLSCs. In vivo experiments further confirmed that Cu-DBs could effectively stimulate the osteogenesis of a rat skull defect and promote angiogenesis, significantly inhibit the inflammatory responses to bone damages, and reduce the infiltration of inflammatory immune cells to the lesion site. Due to the unique chemical characteristics of Si4+ and Cu2+ ions, the Cu-DBs composite biomaterial could enhance the osteogenic differentiation of PDLSCS in vitro, as well as stimulate the osteogenesis of the rat in vivo.

Carboxymethyl chitin or chitosan for osteoinduction effect on the human periodontal ligament stem cells.

Human periodontal ligament stem cells (hPDLSCs) are seeding cells for tissue-engineered treatment of alveolar bone regeneration. To elucidate carboxymethyl chitosan (CMCTS) and carboxymethyl chitin (CMCT) effect on osteogenic differentiation, hPDLSCs were isolated and treated with CMCTS or CMCT. Cell viability and multiplication capacity were measured. The expression of classic osteogenic related molecules, including Alkaline Phosphatase (ALP), Phosphoprotein 1 (OPN), RUNX family transcription factor 2 (Runx2) and Osteocalcin (OCN), were determined. Mineralization levels were detected by Alizarin Red staining. Results showed that both CMCTS and CMCT treatment had the maximal promoting ability for hPDLSCs viability below the concentration of 100 µg/mL, while CMCTS improved hPDLSCs mineralization significantly. CMCTS induced multiple-factor high expression, including ALP, Runx2, OPN and OCN, whereas slightly osteoinductive bioactivity of CMCT was mainly due to ALP. Therefore, CMCTS had a more significant advantage for osteoinductive differentiation of hPDLSCs than CMCT, which may be a promising material for periodontal regeneration.

Isoliquiritigenin alleviates P. gingivalis-LPS/ATP-induced pyroptosis by inhibiting NF-κB/ NLRP3/GSDMD signals in human gingival fibroblasts.

OBJECTIVE: To investigate whether pyroptosis is induced by Porphyromonas gingivalis-lipopolysaccharide (P. gingivalis-LPS)/ adenosine triphosphate (ATP) through NF-κB/NLRP3/GSDMD signaling in human gingival fibroblasts (HGFs) and whether isoliquiritigenin (ISL) alleviates pyroptosis by inhibition of NF-κB/NLRP3/GSDMD signals. DESIGN: Periodontitis was optimally simulated using a combination of P. gingivalis-LPS and ATP. The expression levels of genes and proteins of NF-κB, NLRP3 inflammasome, GSDMD, and IL-1ß was characterized by qRT-PCR, western blotting and ELISA. The 2',7'­dichlorodihydrofluorescein diacetate fluorescence probe was used to determine the intracellular ROS level. Hoechst 33342 and PI double staining, cytotoxicity assay, and caspase-1 activity assay were used to confirm the influence of ISL on pyroptosis in P. gingivalis-LPS/ATP-treated HGFs. RESULTS: P. gingivalis-LPS/ATP stimulation significantly promoted expression of NF-κB, the NLRP3 inflammasome, GSDMD, and IL-1ß at gene and protein levels. The proportion of membrane-damaged cells, caspase-1 activity, and the release of lactate dehydrogenase (LDH) were also elevated. However, pretreatment with ISL observably suppressed these effects. CONCLUSIONS: P. gingivalis-LPS/ATP induced pyroptosis in HGFs by activating NF-κB/NLRP3/GSDMD signals and ISL attenuated P. gingivalis-LPS/ATP-induced pyroptosis by inhibiting these signals. This evidence may provide a new direction for the treatment of periodontitis.

Hypoxia and Porphyromonas gingivalis-lipopolysaccharide synergistically induce NLRP3 inflammasome activation in human gingival fibroblasts.

OBJECTIVE: To investigate the effects of hypoxia and Porphyromonas gingivalis- lipopolysaccharide (P. gingivalis-LPS) on activation of the NACHT leucine-rich repeat protein 3 (NLRP3) inflammasome in human gingival fibroblasts (HGFs). DESIGN: Periodontitis was optimally simulated using a hypoxic concentration of 1%. HGFs were stimulated using P. gingivalis-LPS (1.0 µg/ml) in normoxia and hypoxia for 3 h and 6 h, respectively. The expression levels of genes and proteins of hypoxia-inducible factor-1α (HIF-1α), interleukin-1ß, gasdermin D (GSDMD) and the NLRP3 inflammasome, including NLRP3, apoptosis-associated speck-like protein containing CARD (ASC), caspase-1 and its activated forms, were measured using quantitative real-time polymerase chain reaction and western blot. ELISA was used to detect and determine levels of the inflammatory factor interleukin-1ß in cell supernatants. Lactate dehydrogenase (LDH) release assay, caspase-1 activity assay and Hoechst 33342/Propidium Iodide (PI) staining were performed to further verify the presence of pyroptosis. RESULTS: The NLRP3 inflammasome (i.e., NLRP3, ASC, caspase-1) was not affected by individual stimulation using P. gingivalis-LPS or hypoxia. However, the combination of both hypoxia and P. gingivalis-LPS stimulation significantly enhanced inflammasome activation and promoted the expression of interleukin-1ß, gasdermin D and HIF-1α at gene and protein levels; PI positive cells and the release of LDH were also elevated. CONCLUSION: Hypoxia and P. gingivalis-LPS synergistically induced NLRP3 inflammasome activation in HGFs, and subsequently high levels of interleukin-1ß and GSDMD-mediated pyroptosis can cause an HGF inflammatory response, which plays an important role in the pathogenesis of periodontitis.

Analysis of risk factors for perioperative death in patients undergoing aortic valve replacement using biological valves.

BACKGROUND: Aortic valve disease has become one of the important factors affecting human health. Aortic valve disease is a progressive disease, if not actively treated, the prognosis is poor. Aortic valve replacement (AVR) surgery is an important treatment for aortic valve disease. At present, the AVR surgery using biological valve accounts for about 40% of the total number of AVR surgery. There are still more perioperative deaths in China due to the large number of AVR patients using biological valves. The objective of this study is to explore measures to reduce perioperative mortality of patients after AVR surgery with biological valves. METHODS: The clinical data of patients undergoing AVR surgery with biological valves in Affiliated Hospital of Qingdao University from November 15, 2020 to December 31, 2022 were reviewed and analyzed. Patients were divided into death group and survival group according to their perioperative survival. Risk factors that may influence perioperative mortality were analyzed and compared between the 2 groups. DISCUSSION: This study was a retrospective analysis of risk factors that may influence perioperative mortality in patients undergoing AVR surgery using biological valves. The conclusions of this study can be used to guide clinical decisions-making and relevant guidelines-developing for perioperative treatment of patients undergoing AVR surgery using biological valves.

The effect of doxycycline-containing chitosan/carboxymethyl chitosan nanoparticles on NLRP3 inflammasome in periodontal disease.

A polyelectrolyte complex nanoparticle comprising chitosan (CS) and carboxymethyl chitosan (CMCS) was prepared (CS/CMCS-NPs) by ionic gelation, which was then used as a doxycycline carrier (Dox:CS/CMCS-NPs). The obtained CS/CMCS-NPs and Dox:CS/CMCS-NPs were characterized for various parameters and bacteriostatic ability against Porphyromonas gingivalis. The regulation of related genes and proteins of NLRP3 inflammasome and IL-1ß in human gingival fibroblasts (HGFs) was characterized by qRT-PCR, western blotting and ELISA. The results showed that Dox:CS/CMCS-NPs had an orderly morphology and an excellent cytocompatibility. P. gingivalis was strongly inhibited by Dox:CS/CMCS-NPs contrasted with control group. Dox:CS/CMCS-NPs effectively down-regulated both gene and protein levels of NLRP3 inflammasome and IL-1ß in HGFs. This study provides a new method for rational application of Dox in the clinical treatment of periodontal disease and a new direction for explaining the mechanism of action of Dox:CS/CMCS-NPs and more drug-carrying nanoparticles.

Biological effects on tooth root surface topographies induced by various mechanical treatments.

The cleaning and physicochemical properties on tooth root biointerfaces are pivotal for periodontal healing. Herein, this work investigated the impact of multi-treatment on the physicochemical features of tooth root surfaces and the responsive behavior of human gingival fibroblasts (hGFs). It was found that the combination of various mechanical treatments significantly affects the topographical pattern and size as well as wettability on tooth root surfaces. Furthermore, biological experiments revealed that hGF behaviors (i.e., cell adhesion, shape, spreading, arrangement, and viability) were regulated by the topography and wettability of tooth root surfaces. Also, there was no significant difference in the protein expression of NLRP3 inflammasome and IL-1ß in hGFs among tooth root surfaces under various treatments. This study provides new insights to efficiently remove the dental calculus and to understand the interaction between the tooth root interface and cell, which could guide the clinical operation and thereby is more conducive to periodontal recovery.

Role of gingival mesenchymal stem cell exosomes in macrophage polarization under inflammatory conditions.

OBJECTIVE: Exosomes have been shown to play a strong role in intercellular communication. While GMSCs have been extensively studied, less research exists on exosomes derived from GMSCs, especially on how exosomes affect macrophages. This study aimed to investigate the impact of GMSC-derived exosomes on macrophage polarization and phenotype under inflammatory conditions. METHODS: Exosomes were isolated from GMSCs-conditioned media by ultracentrifugation (UC) and characterized by transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA) and western blot (WB). In vitro, GMSC-derived exosomes were co-incubated with macrophages for 24 h in the absence or presence of M1 polarizing conditions in the six-well plate. The protein and mRNA expression levels of M1 and M2 macrophage markers were detected and the supernatants were collected for an enzyme-linked immunosorbent assay (ELISA). RESULTS: Exosomes were successfully isolated from GMSCs. Macrophages co-cultured with exosomes showed significantly decreased levels of the M1 markers Tumor Necrosis Factor-α (TNF-α), Interleukin-12 (IL-12), CD86 and Interleukin-1ß (IL-1ß). By contrast, M2 marker Interleukin-10 (IL-10) levels moderately increased. Meanwhile, similar results were acquired in the cell culture supernatants. CONCLUSION: GMSC-derived exosomes may promote M1 macrophage transformation into M2 macrophages, reducing the pro-inflammatory factors produced by M1 macrophages.

TGF­ß induces periodontal ligament stem cell senescence through increase of ROS production.

Periodontal ligament stem cells (PDLSCs) are vital for the regeneration of periodontal tissue. Transforming growth factor (TGF) ß1, a potent stimulator of tissue regeneration, is extensive and abundant in the bone matrix. However, the effect of TGF­ß1 in periodontal differentiation remains to be elucidated. The present study aimed to evaluate the effect of TGF­ß1 on human PDLSCs. PDLSCs were isolated using CD146 microbeads, and characterized by flow cytometry. The present study demonstrated that treatment with TGF­ß1 induced PDLSC senescence, characterized by increases in senescence­associated beta­galactosidase activity and elevation of both p16 and p21 expression. Furthermore, TGF­ß1 treatment demonstrated the capacity to induce the production of reactive oxygen species (ROS). Of note, addition of a ROS scavenger successfully rescued the TGF­ß1­induced PDLSC senescence. Thus, the present results indicated that TGF­ß1 may serve a vital role in PDLSC senescence, and thus represent a potential target involved in the fabrication and formation of hard tissue for clinical treatment.

Doxycycline inhibits NAcht Leucine-rich repeat Protein 3 inflammasome activation and interleukin-1ß production induced by Porphyromonas gingivalis-lipopolysaccharide and adenosine triphosphate in human gingival fibroblasts.

OBJECTIVE: To investigate the effect of adenosine triphosphate (ATP) on inflammasome activation by Porphyromonas gingivalis-lipopolysaccharide (P. gingivalis-LPS) stimulation and the anti-inflammatory eff ;ect of doxycycline (Dox) in human gingival fibroblasts (HGFs). DESIGN: The optimal concentration of P. gingivalis-LPS (1.0 µg/mL) for cellular viability was determined by observing cell morphology and measuring the amount of formazan and the expression of pro-caspase-1. The expression of genes and proteins related to the NAcht Leucine-rich repeat Protein 3 (NLRP3) inflammasome, including NLRP3, apoptosis-associated speck-like protein containing CARD (ASC), caspase-1 and its activated forms, and the inflammatory factor interleukin-1ß (IL-1ß) and its activated forms were measured. RESULTS: The NLRP3 inflammasome (i.e., NLRP3, ASC, caspase-1) was not affected by stimulation with P. gingivalis-LPS or ATP. However, a combination of P. gingivalis-LPS and ATP significantly enhanced inflammasome activation and IL-1ß production at the gene and protein levels as measured by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot, respectively. Furthermore, doxycycline addition markedly inhibited inflammasome activation and IL-1ß production induced by a combination of P. gingivalis-LPS and ATP. CONCLUSIONS: LPS, ATP, and doxycycline play critical roles in regulating host immune responses. This evidence provides guidance for the application of tetracycline drugs for the clinical treatment of periodontal disease.

Stretching magnitude-dependent inactivation of AKT by ROS led to enhanced p53 mitochondrial translocation and myoblast apoptosis.

Previously, we had shown that high magnitude stretch (HMS), rather than low magnitude stretch (LMS), induced significant apoptosis of skeletal muscle C2C12 myoblasts. However, the molecular mechanism remains obscure. In this study, we found that p53 protein accumulated in the nucleus of LMS-loaded cells, whereas it translocated into mitochondria of HMS-loaded cells. Knocking down endogenous p53 by shRNA abrogated HMS-induced apoptosis. Furthermore, we demonstrated that overaccumulation of reactive oxygen species (ROS) during HMS-inactivated AKT that was activated in LMS-treated cells, which accounted for the distinct p53 subcellular localizations under HMS and LMS. Blocking ROS generation by N-acetylcysteine (NAC) or overexpressing constitutively active AKT vector (CA-AKT) inhibited HMS-incurred p53 mitochondrial translocation and promoted its nuclear targeting. Moreover, both NAC and CA-AKT significantly attenuated HMS-induced C2C12 apoptosis. Finally, we found that Ser389 phosphorylation of p53 was a downstream event of ROS-inactivated AKT pathway, which was critical to p53 mitochondrial trafficking during HMS stimuli. Transfecting p53-shRNA C2C12s with the mutant p53 (S389A) that was unable to target p53 to mitochondria underwent significantly lower apoptosis than transfection with wild-type p53. Altogether, our study uncovered that mitochondrial localization of p53, resulting from p53 Ser389 phosphorylation through ROS-inactivated AKT pathway, prompted C2C12 myoblast apoptosis during HMS stimulation.

Characteristics of chitosan-modified glass ionomer cement and their effects on the adhesion and proliferation of human gingival fibroblasts: an in vitro study.

This study explores the possibility of adhering gingival tissue to a root surface that was restored with chitosan (CS)-modified glass ionomer cement (GIC) in the case of gingival recessions associated with root caries, which provides a theoretical basis for clinical application at the cellular level. The specimens were mixed after integrating 1, 2, and 4 wt% CS into the GIC fluid. The characteristics and cytocompatibility were then examined. As more CS was incorporated into the GIC fluid, the mechanical properties and cytocompatibility of chitosan-modified glass ionomer cement (CS-GIC) first improved but then reduced. Under scanning electron microscopy, microcracks were observed on the surface of all materials, but the fewest microcracks were observed on the surface of 2 wt% CS-GIC. The compressive strength of 2 wt% CS-GIC was significantly higher than that of the other groups at 5 days (P < 0.05) and the addition of chitosan didn't change the basic fracture mode of materials. Additionally, the integration 2 wt% CS into GIC can obviously reduce acidity of the original GIC (P < 0.01) when using extracts with concentrations of 100 and 50%. The Cell Counting Kit-8 assay and adhesion and proliferation of human gingival fibroblasts (HGFs) on the surface of the materials indicated that 2 wt% CS-GIC presented better cytocompatibility and was more suitable for the growth of HGFs. In summary, 2 wt% CS-GIC could be considered as a potential root filling material to allow the adhesion and growth of gingival tissue.

JAK2/STAT3 is associated with the inflammatory process in periapical granuloma.

OBJECTIVE: It has been shown that JAK2/STAT3 is involved in the occurrence of various inflammatory diseases. The purpose of this study was to associate the expression of Janus kinase 2 (JAK2) and its receptor signal transducer and activator of transcription 3 (STAT3) and suppressors of cytokine signaling 3 (SOCS3), to periapical granuloma. METHODS: Samples were collected from 40 patients who were divided into two groups, namely, healthy control (N=20) and periapical granuloma (N=20) groups in accordance with classified standards. The samples were prepared for histological analysis, immunohistochemistry, and double immunofluorescence staining. RESULTS: Only slight inflammatory cell infiltration was observed in the tissues from the healthy control group. Extensive infiltration of inflammatory cells was observed in patients with chronic periapical disease. The periapical granuloma group had higher levels of JAK2, STAT3, p-JAK2, p-STAT3 and SOCS3 (all P<0.05) than the control group. Double immunofluorescence staining results showed the presence of JAK2-positive and STAT3-positive cells in the periapical lesion areas. CONCLUSIONS: This study demonstrated that JAK2, STAT3, and SOCS3 can be observed and may be associated with the inflammatory process in periapical lesions. The results of this study will provide new insights into the pathological mechanisms of human periapical granuloma.

A novel pH-responsive quaternary ammonium chitosan-liposome nanoparticles for periodontal treatment.

The aim of this study was to evaluate the antibacterial activity and cytocompatibility of novel pH-activated nanoparticles (NPs) in vitro and in vivo. The NPs were synthesized from a quaternary ammonium chitosan, i.e., N,N,N-trimethyl chitosan, a liposome, and doxycycline (TMC-Lip-DOX NPs). The cytocompatibility of the NPs was evaluated. The TMC-Lip-DOX NPs achieved superb inhibition of free mixed bacteria and biofilm formation. They also showed excellent biocompatibility with human periodontal ligament fibroblasts. Animal experiments showed that the NPs strongly inhibited biofilm formation and prevented alveolar bone absorption in vivo. All the results indicate that the TMC-Lip-DOX NPs have good potential for use in the treatment of periodontal and other inflammatory diseases.

Refinement and Evaluation of Modified Minimally Invasive Harvest Technique for Subepithelial Connective Tissue.

INTRODUCTION: The aim of this paper was to refine the modified minimally invasive single-incision technique (MSIT) into 6 steps that are easy to execute. The advantage of this modification was evaluated and compared with the traditional trap-door incision technique (TDIT). Several other harvesting techniques, suturing techniques, indications, contraindications, and limitations were also summarized. MATERIALS AND METHODS: A total of 40 patients presenting with multiple areas of gingival recession were recruited for this study. All patients were randomly assigned to either the MSIT or TDIT group. Standard periodontal instruments and crossed horizontal suspension sutures were used for both procedures. Harvesting and suturing time, verbal rating scale (VRS), and an early wound-healing index (EHI) were recorded. RESULTS: The total operating time, and particularly the suturing time, was shorter in the MSIT group (267.70 ±â€Š20.24 seconds) than the TDIT group (298.20 ±â€Š21.07 seconds), and the difference was statistically significant (P < 0.05). However, there was no significant difference in pain level between the 2 groups according to the VRS evaluation (P = 0.3658). One week postsurgery, the EHI of the MSIT group (2.00 ±â€Š0.95) was significantly lower than the TDIT group (2.85 ±â€Š1.15) (P < 0.05). DISCUSSION: The 6-step MSIT is more predictable and easy to execute, which decreases the challenge for both dentists and patients. Favorable outcomes occurred because of the streamlined minimally invasive procedure and favorable postoperative recovery.

Cleavage of caspase-12 at Asp94, mediated by endoplasmic reticulum stress (ERS), contributes to stretch-induced apoptosis of myoblasts.

Mechanical overloading can lead to skeletal muscle damage instead of remodeling. This is attributed to the excessive apoptosis of myoblasts, mechanism of which remains to be elucidated. The present study aimed to investigate the involvement of endoplasmic reticulum stress (ERS) and caspase-12 in mediating the stretch-induced apoptosis of myoblasts. Myoblast apoptosis was evaluated by Hoechst staining, DNA fragmentation assay, Annexin V binding, and propidium iodide staining, as well as caspase-3 and poly-ADP-ribose polymerase 1 cleavage. First, our results showed that apoptosis was elevated in a time-dependent manner when myoblasts were subjected to cyclic mechanical stretch (CMS) for 12, 24, and 36 hr. Concomitantly, CMS triggered the ERS and caspase-12 cleavage; ERS inhibitor GSK 2606414 suppressed the CMS-induced cleavage of caspase-12 and myoblast apoptosis. Silencing caspase-12 attenuated the apoptosis of myoblasts under CMS. Furthermore, CMS-induced myoblast apoptosis was partially recovered by overexpressing wild-type caspase-12 in caspase-12-silenced myoblasts. In contrast, overexpressing mutant caspase-12 (D94N), which cannot be cleaved into the active caspase-12 fragments, failed to accomplish the same effect. Finally, C2C12 overexpressing truncated caspase-12 segment (TC-casp12-D94), which starts from Asp94 and ends at Asn419, underwent apoptosis under both static and stretched conditions. Interestingly, C2C12 myoblasts seemed to be resistant to stretch-induced apoptosis upon low-serum-induced differentiation. In conclusion, our study provided evidence that caspase-12 cleavage at Asp94, induced by ERS under mechanical stimuli, is the key molecule in initiating the stretch-triggered apoptosis of myoblasts.

pH-Activated nanoparticles with targeting for the treatment of oral plaque biofilm.

Oral plaque biofilms are highly resilient microbial assemblies that are challenging to eradicate. Herein, we describe the synthesis and study of pH-positive, doxycycline (DOX)-loaded nanocarriers to combat pathogenic biofilms. The mixed shell-core nanoparticles consisted of quaternary ammonium chitosan (TMC) as a positively charged section, which targeted nanoparticles to negatively charged biofilm surfaces. In addition liposomes were used as a DOX loading tool to eradicate the multidrug-resistant biofilm. In a drug release test, DOX release was pH-dependent with t1/2 = 0.75 h and 2.3 h for release at pH 4.5 and 6.8, respectively. Furthermore, TMC-Lip-DOX NPs could adhere to the biofilm and efficiently remove the biofilm from the hydroxyapatite (HA) surface. Furthermore, TMC-Lip-DOX NPs had biocomaptible properties and were non-toxic to MC3T3-E1 cells. This constitutes a highly effective pathway to control oral plaque biofilms and has a good potential use for dental biofilm therapies.

An experimental hyperlipidemia model with periodontitis in mice.

PURPOSE: In many animal models and clinical trials, the relationship between periodontitis and hyperlipidemia is bidirectional and interlinked. In this study, an experimental hyperlipidemia model with periodontitis in mice is introduced. METHODS: C57BL/6J mice were assigned into group A and B and Apolipoprotein E-deficient (ApoE-/-) mice into group C. After 4 weeks of a high fat diet (HFD), group B and C were ligated on the maxillary second molar tooth, and mice were sacrificed after 8 weeks of the HFD. Levels of lipids, interleukin (IL)-6, IL-10, and tumor necrosis factor (TNF)-α in serum after 0, 4, and 8 weeks were determined. Alveolar bone loss (ABL) was assessed under stereomicroscope. Maxillary bones and atherosclerotic lesion area in the aorta were collected for hematoxylin and eosin (HE) staining. RESULTS: After feeding with a HFD for 4 weeks, group C demonstrated dramatic increases in serum lipid levels. The ABL and levels of IL-6, IL-10, and TNF-α in group C was significantly higher than those of group A and B (P<0.05). Atherosclerotic lesions were observed in group C. CONCLUSIONS: These data demonstrate that an experimental hyperlipidemia model with periodontitis in mice is successfully established by ligation in ApoE-/- mice. This method is economical and time saving, and worthy of more general application.