RESUMO
Fracture of the alveolar bone resorption is a common complication in orthodontic treatment, which mainly caused by extreme mechanical loading. However, the ferroptosis with orthodontic tooth movement(OTM) relationship has not been thoroughly described. We here analysed whether ferroptosis is involved in OTM-associated alveolar bone loss. Mouse osteoblasts (MC-3T3) and knockdown glutathione peroxidase 4 (GPX4) MC-3T3 were stimulated with compressive force loading and ferrostatin-1 (Fer-1, a ferroptosis inhibitor), and the changes in lipid peroxidation morphology, expression of ferroptosis-related factors and osteogenesis levels were detected. After establishing the rat experimental OTM model, the changes in ferroptosis-related factors and osteogenesis levels were reevaluated in the same manner. Ferroptosis was involved in mechanical stress regulating osteoblast remodelling, and Fer-1 and erastin affected osteoblasts under compression force loading. Fer-1 regulated ferroptosis and autophagy in MC-3T3 and promoted bone proliferation. GPX4-dependent ferroptosis stimulated the YAP (homologous oncoproteins Yes-associated protein) pathway, and GPX4 promoted ferroptosis via the YAP-TEAD (transcriptional enhanced associate domain) signal pathway under mechanical compression force. The in vivo experiment results were consistent with the in vitro experiment results. Ferroptosis transpires during the motion of orthodontic teeth, with compression force side occurring earlier than stretch side within 4 h. GPX4 plays an important role in alveolar bone loss, while Fer-1 can inhibit the compression force-side alveolar bone loss. GPX4's Hippo-YAP pathway is activated by the lack of compression force in the lateral alveolar bone.
Assuntos
Perda do Osso Alveolar , Ferroptose , Camundongos , Ratos , Animais , Osteogênese/fisiologia , Estresse Mecânico , Transdução de SinaisRESUMO
Periodontitis is associated with significant alveolar bone loss. Patients with iron overload suffer more frequently from periodontitis, however, the underlying mechanisms remain largely elusive. Here, we investigated the role of transferrin receptor 2 (Tfr2), one of the main regulators of iron homeostasis, in the pathogenesis of periodontitis and the dental phenotype under basal conditions in mice. As Tfr2 suppresses osteoclastogenesis, we hypothesized that deficiency of Tfr2 may exacerbate periodontitis-induced bone loss. Mice lacking Tfr2 (Tfr2-/- ) and wild-type (Tfr2+/+ ) littermates were challenged with experimental periodontitis. Mandibles and maxillae were collected for microcomputed tomography and histology analyses. Osteoclast cultures from Tfr2+/+ and Tfr2-/- mice were established and analyzed for differentiation efficiency, by performing messenger RNA expression and protein signaling pathways. After 8 days, Tfr2-deficient mice revealed a more severe course of periodontitis paralleled by higher immune cell infiltration and a higher histological inflammation index than Tfr2+/+ mice. Moreover, Tfr2-deficient mice lost more alveolar bone compared to Tfr2+/+ littermates, an effect that was only partially iron-dependent. Histological analysis revealed a higher number of osteoclasts in the alveolar bone of Tfr2-deficient mice. In line, Tfr2-deficient osteoclastic differentiation ex vivo was faster and more efficient as reflected by a higher number of osteoclasts, a higher expression of osteoclast markers, and an increased resorptive activity. Mechanistically, Tfr2-deficient osteoclasts showed a higher p38-MAPK signaling and inhibition of p38-MAPK signaling in Tfr2-deficient cells reverted osteoclast formation to Tfr2+/+ levels. Taken together, our data indicate that Tfr2 modulates the inflammatory response in periodontitis thereby mitigating effects on alveolar bone loss.
Assuntos
Perda do Osso Alveolar , Periodontite , Animais , Humanos , Camundongos , Perda do Osso Alveolar/genética , Perda do Osso Alveolar/metabolismo , Ferro , Osteoclastos , Periodontite/genética , Periodontite/metabolismo , Receptores da Transferrina/genética , Microtomografia por Raio-X , Camundongos Endogâmicos C57BL , Células CultivadasRESUMO
Bone defects are characterized by a hypoxic environment, which affects bone tissue repair. However, the role of hypoxia in the repair of alveolar bone defects remains unclear. Human periodontal ligament stem cells (hPDLSCs) are high-quality seed cells for repairing alveolar bone defects, whose behavior changes under hypoxia. However, their mechanism of action is not known and needs to be elucidated. We hypothesized that hypoxia might be beneficial to alveolar bone defect repair and the osteogenic differentiation of hPDLSCs. To test this hypothesis, cobalt chloride (CoCl2) was used to create a hypoxic environment, both in vitro and in vivo. In vitro study, the best osteogenic effect was observed after 48 h of hypoxia in hPDLSCs, and the AKT/mammalian target of rapamycin/eukaryotic translation initiation factor 4e-binding protein 1 (AKT/mTOR/4EBP-1) signaling pathway was significantly upregulated. Inhibition of the AKT/mTOR/4EBP-1 signaling pathway decreased the osteogenic ability of hPDLSCs under hypoxia and hypoxia-inducible factor 1 alpha (HIF-1α) expression. The inhibition of HIF-1α also decreased the osteogenic capacity of hPDLSCs under hypoxia without significantly affecting the level of phosphorylation of AKT/mTOR/4EBP-1. In vitro study, Micro-CT and tissue staining results show better bone regeneration in hypoxic group than control group. These results suggested that hypoxia promoted alveolar bone defect repair and osteogenic differentiation of hPDLSCs, probably through AKT/mTOR/4EBP-1/HIF-1α signaling. These findings provided important insights into the regulatory mechanism of hypoxia in hPDLSCs and elucidated the effect of hypoxia on the healing of alveolar bone defects. This study highlighted the importance of physiological oxygen conditions for tissue engineering.
Assuntos
Perda do Osso Alveolar , Diferenciação Celular , Hipóxia Celular , Cobalto , Subunidade alfa do Fator 1 Induzível por Hipóxia , Osteogênese , Ligamento Periodontal , Humanos , Proteínas Adaptadoras de Transdução de Sinal/efeitos dos fármacos , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Perda do Osso Alveolar/metabolismo , Regeneração Óssea/efeitos dos fármacos , Proteínas de Ciclo Celular/metabolismo , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Cobalto/farmacologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Osteogênese/efeitos dos fármacos , Ligamento Periodontal/metabolismo , Ligamento Periodontal/citologia , Fosfoproteínas/metabolismo , Proteínas Proto-Oncogênicas c-akt/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Células-Tronco/metabolismo , Serina-Treonina Quinases TOR/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismoRESUMO
OBJECTIVE: The objective of the study was to evaluate the expression of oxytocin receptors in normal and inflamed gingiva, as well as the effects of systemic administration of oxytocin in bone loss and gum inflammatory mediators in a rat model of experimental periodontitis. BACKGROUND DATA: Current evidence supports the hypothesis of a disbalance between the oral microbiota and the host's immune response in the pathogenesis of periodontitis. Increased complexity of the microbial biofilm present in the periodontal pocket leads to local production of nitrogen and oxygen-reactive species, cytokines, chemokines, and other proinflammatory mediators which contribute to periodontal tissue destruction and bone loss. Oxytocin has been suggested to participate in the modulation of immune and inflammatory processes. We have previously shown that oxytocin, nitric oxide, and endocannabinoid system interact providing a mechanism of regulation for systemic inflammation. Here, we aimed at investigating not only the presence and levels of expression of oxytocin receptors on healthy and inflamed gingiva, but also the effects of oxytocin treatment on alveolar bone loss, and systemic and gum expression of inflammatory mediators involved in periodontal tissue damage using ligature-induced periodontitis. Therefore, anti-inflammatory strategies oriented at modulating the host's immune response could be valuable adjuvants to the main treatment of periodontal disease. METHODS: We used an animal model of ligature-induced periodontitis involving the placement of a linen thread (Barbour flax 100% linen suture, No. 50; size 2/0) ligature around the neck of first lower molars of adult male rats. The ligature was left in place during the entire experiment (7 days) until euthanasia. Animals with periodontitis received daily treatment with oxytocin (OXT, 1000 µg/kg, sc.) or vehicle and/or atosiban (3 mg/kg, sc.), an antagonist of oxytocin receptors. The distance between the cement-enamel junction and the alveolar bone crest was measured in stained hemimandibles in the long axis of both buccal and lingual surfaces of both inferior first molars using a caliper. TNF-α levels in plasma were determined using specific rat enzyme-linked immunosorbent assays (ELISA). OXT receptors, IL-6, IL-1ß, and TNF-α expression were determined in gingival tissues by semiquantitative or real-time PCR. RESULTS: We show that oxytocin receptors are expressed in normal and inflamed gingival tissues in male rats. We also show that the systemic administration of oxytocin prevents the experimental periodontitis-induced increased gum expression of oxytocin receptors, TNF-α, IL-6, and IL-1ß (p < .05). Furthermore, we observed a reduction in bone loss in rats treated with oxytocin in our model. CONCLUSIONS: Our results demonstrate that oxytocin is a novel and potent modulator of the gingival inflammatory process together with bone loss preventing effects in an experimental model of ligature-induced periodontitis.
Assuntos
Perda do Osso Alveolar , Periodontite , Ratos , Masculino , Animais , Ocitocina/uso terapêutico , Ocitocina/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Receptores de Ocitocina/metabolismo , Modelos Animais de Doenças , Periodontite/metabolismo , Gengiva/metabolismo , Perda do Osso Alveolar/tratamento farmacológico , Perda do Osso Alveolar/prevenção & controle , Perda do Osso Alveolar/etiologia , Processo Alveolar/metabolismo , Mediadores da Inflamação/metabolismoRESUMO
OBJECTIVE: The aim of this study was to investigate the association between autoinducer-2 (AI-2) of oral microbial flora and the alveolar bone destruction in periodontitis to determine if AI-2 may have the potential that monitor periodontitis and predict bone loss. BACKGROUND: Plaque biofilm was the initiating factor of periodontitis and the essential factor of periodontal tissue destruction. The formation of biofilms depended on the complex regulation of the quorum sensing (QS) system, in which bacteria could sense changes in surrounding bacterial density by secreting the autoinducer (AI) to regulate the corresponding physiological function. Most oral bacteria also communicated with each other to form biofilms administrating the QS system, which implied that the QS system of periodontal pathogens was related to periodontitis, but the specific relationship was unknown. METHOD: We collected the gingival crevicular fluid (GCF) samples and measured the concentration of AI-2 in samples using the Vibrio harveyi BB180 bioluminescent-reporter system. To explore the interaction between AI-2 and bone metabolism, we utilized AI-2 purified from Fusobacterium nucleatum to investigate the impact of F. nucleatum AI-2 on osteoclast differentiation. Moreover, we constructed murine periodontitis models and multi-species biofilm models to study the association between AI-2 and periodontal disease progression. RESULTS: The AI-2 concentration in GCF samples increased along with periodontal disease progression (p < .0001). F. nucleatum AI-2 promoted osteoclast differentiation in a dose-dependent manner. In the periodontitis mice model, the CEJ-ABC distance in the F. nucleatum AI-2 treatment group was higher than that in the simple ligation group (p < .01), and the maxilla of the mice in the group exhibited significantly lower BMD and BV/TV values (p < .05). CONCLUSIONS: We demonstrated that the AI-2 concentration varied with the alveolar bone destruction in periodontitis, and it may have the potential for screening periodontitis. F. nucleatum AI-2 promoted osteoclast differentiation in a dose-dependent manner and aggravated bone loss.
Assuntos
Perda do Osso Alveolar , Biofilmes , Fusobacterium nucleatum , Homosserina , Lactonas , Periodontite , Perda do Osso Alveolar/microbiologia , Perda do Osso Alveolar/metabolismo , Periodontite/microbiologia , Animais , Homosserina/análogos & derivados , Homosserina/metabolismo , Biofilmes/crescimento & desenvolvimento , Camundongos , Humanos , Líquido do Sulco Gengival/microbiologia , Líquido do Sulco Gengival/química , Masculino , Modelos Animais de Doenças , Osteoclastos , Percepção de Quorum , Feminino , Adulto , Diferenciação Celular , Pessoa de Meia-Idade , Microtomografia por Raio-XRESUMO
BACKGROUND: Periodontitis is a chronic inflammatory disease defined by the pathologic loss of the periodontal ligament and alveolar bone in relation to aging. Although clinical cohort studies reported that periodontitis is significantly elevated in males compared to females, emerging evidence indicates that females with dementia are at a greater risk for periodontitis and decreased alveolar bone. OBJECTIVE: This study aimed to evaluate whether dementia is a potential sex-dependent risk factor for periodontal bone loss using an experimental model of periodontitis induced in the triple transgenic (3x-Tg) dementia-like mice and clinical samples collected from senior 65 plus age patients with diagnosed dementia. MATERIALS AND METHODS: We induced periodontitis in dementia-like triple-transgenic (3x-Tg) male and female mice and age-matched wild-type (WT) control mice by ligature placement. Then, alveolar bone loss and osteoclast activity were evaluated using micro-CT and in situ imaging assays. In addition, we performed dental examinations on patients with diagnosed dementia. Finally, dementia-associated Aß42 and p-Tau (T181) and osteoclastogenic receptor activator of nuclear factor kappa-Β ligand (RANKL) in gingival crevicular fluid (GCF) collected from mice and clinical samples were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: Alveolar bone loss and in situ osteoclast activity were significantly elevated in periodontal lesions of 3x-Tg females but not males, compared to wild-type control mice. In addition, we also observed that the probing pocket depth (PPD) was also significantly elevated in female patients with dementia. Using ELISA assay, we observed that females had elevated levels of osteoclastogenic RANKL and dementia-associated Aß42 and p-Tau (T181) in the GCF collected from experimental periodontitis lesions and clinical samples. CONCLUSION: Altogether, we demonstrate that females with dementia have an increased risk for periodontal bone loss compared to males.
Assuntos
Perda do Osso Alveolar , Demência , Modelos Animais de Doenças , Camundongos Transgênicos , Periodontite , Ligante RANK , Animais , Feminino , Perda do Osso Alveolar/patologia , Perda do Osso Alveolar/diagnóstico por imagem , Perda do Osso Alveolar/metabolismo , Masculino , Camundongos , Demência/etiologia , Humanos , Idoso , Ligante RANK/análise , Ligante RANK/metabolismo , Fatores Sexuais , Periodontite/complicações , Periodontite/patologia , Microtomografia por Raio-X , Osteoclastos/patologia , Peptídeos beta-Amiloides/metabolismo , Líquido do Sulco Gengival/química , Fragmentos de Peptídeos/análise , Fatores de RiscoRESUMO
BACKGROUND AND OBJECTIVE: Clinical studies found high levels of hepatocyte growth factor (HGF) expression in patients with periodontitis. Studies suggest that HGF plays an important role in periodontitis, is involved in inflammation, and modulates alveolar bone integrity in periodontitis. This study aims to investigate the effects and mechanisms of HGF in the progression of experimental periodontitis. METHODS: We used silk thread ligation to induce periodontitis in HGF-overexpressing transgenic (HGF-Tg) and wild-type C57BL/6J mice. The effects of HGF overexpression on alveolar bone destruction were assessed by microcomputed tomography imaging at baseline and on days 7, 14, 21, and 28. We analyzed the cytokines (IL-6 and TNF-α) and lymphocytes in periodontitis tissues by enzyme-linked immunosorbent assay and flow cytometry. The effects of HGF on alveolar bone destruction were further tested by quantifying the systemic bone metabolism markers CTXI and PINP and by RNA sequencing for the signaling pathways involved in bone destruction. Western blotting and immunohistochemistry were performed to further elucidate the involved signaling pathways. RESULTS: We found that experimental periodontitis increased HGF production in periodontitis tissues; however, the effects of HGF overexpression were inconsistent with disease progression. In the early stage of periodontitis, periodontal inflammation and alveolar bone destruction were significantly lower in HGF-Tg mice than in wild-type mice. In the late stage, HGF-Tg mice showed higher inflammatory responses and progressively aggravated bone destruction with continued stimulation of inflammation. We identified the IL-17/RANKL/TRAF6 pathway as a signaling pathway involved in the HGF effects on the progression of periodontitis. CONCLUSION: HGF plays divergent effects in the progression of experimental periodontitis and accelerates osteoclastic activity and bone destruction in the late stage of inflammation.
Assuntos
Perda do Osso Alveolar , Fator de Crescimento de Hepatócito , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Periodontite , Microtomografia por Raio-X , Animais , Fator de Crescimento de Hepatócito/metabolismo , Periodontite/metabolismo , Periodontite/patologia , Camundongos , Perda do Osso Alveolar/metabolismo , Perda do Osso Alveolar/diagnóstico por imagem , Perda do Osso Alveolar/patologia , Modelos Animais de Doenças , Progressão da Doença , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-6/metabolismo , Transdução de Sinais , Masculino , Ensaio de Imunoadsorção EnzimáticaRESUMO
BACKGROUND AND OBJECTIVE: Periodontitis is intimately associated with the development of various systemic diseases, among which type 2 diabetes mellitus (T2DM) has a bidirectional relationship with the pathogenesis of periodontitis. The objective of the present work was to investigate the role of berberine (BBR) in periodontitis with T2DM and related mechanisms. METHODS: The mRNA expression of macrophage polarization-related factors in the microenvironment of periodontal inflammation was detected using real-time quantitative PCR (RT-qPCR). The experimental periodontitis model was constructed in wild-type (WT) and T2DM (db/db) mice, which were administered BBR after 7 days of modeling. Alveolar bone loss (ABL) in each group of mice was measured utilizing micro-computed tomography images. RT-qPCR was performed to analyze the levels of macrophage polarization-related factors in mouse gingiva. Lastly, using western blotting and RT-qPCR, the signaling pathway of BBR affecting macrophage polarization in the microenvironment of periodontitis was explored. RESULTS: BBR inhibited M1 polarization and stimulated M2 polarization in the periodontitis microenvironment. BBR decreased ABL in the WT and T2DM periodontitis models. And BBR reduced the production of proinflammatory cytokines and increased anti-inflammatory cytokine expression in the gingiva of WT and T2DM model mice. Ultimately, BBR mediates its anti-inflammatory effects on periodontitis through inhibition of the NF-κB pathway. CONCLUSIONS: BBR had a therapeutic effect on T2DM-associated periodontitis via inhibiting the NF-κB pathway to affect macrophage polarization, which may have implications for the new pharmacological treatment of T2DM-associated periodontitis.
Assuntos
Perda do Osso Alveolar , Berberina , Diabetes Mellitus Tipo 2 , Macrófagos , NF-kappa B , Periodontite , Transdução de Sinais , Animais , Periodontite/complicações , Periodontite/tratamento farmacológico , Camundongos , NF-kappa B/metabolismo , Macrófagos/efeitos dos fármacos , Berberina/farmacologia , Berberina/uso terapêutico , Diabetes Mellitus Tipo 2/complicações , Perda do Osso Alveolar/etiologia , Perda do Osso Alveolar/prevenção & controle , Modelos Animais de Doenças , Masculino , Camundongos Endogâmicos C57BL , Microtomografia por Raio-X , Ativação de Macrófagos/efeitos dos fármacos , Citocinas/metabolismo , Diabetes Mellitus Experimental/complicaçõesRESUMO
OBJECTIVE AND BACKGROUND: Psychological stress is a potential modifiable environmental risk factor causally related to the exacerbation of periodontitis and other chronic inflammatory diseases. This animal study aimed to investigate comprehensively the preventive efficacy of systemic melatonin administration on the possible effects of restraint stress on the periodontal structures of rats with periodontitis. METHODS: Forty-eight male Sprague Dawley rats were randomly divided into six groups: control, restraint stress (S), S-melatonin (S-Mel), experimental periodontitis (Ep), S-Ep, and S-Ep-Mel. Periodontitis was induced by placing a 3.0 silk suture in a sub-paramarginal position around the cervix of the right and left lower first molars of the rats and keeping the suture in place for 5 weeks. Restraint stress was applied simultaneously by ligation. Melatonin and carriers were administered to the control, S, Ep, and S-Ep groups intraperitoneally (10 mg/body weight/day, 14 days) starting on day 21 following ligation and subjection to restraint stress. An open field test was performed on all groups on day 35 of the study. Periodontal bone loss was measured via histological sections. Histomorphometric and immunohistochemical (RANKL and OPG) evaluations were performed on right mandibular tissue samples and biochemical (TOS (total oxidant status), TAS (total antioxidant status), OSI (oxidative stress index), IL-1ß, IL-10, and IL-1ß/IL-10) evaluations were performed on left mandibular tissue samples. RESULTS: Melatonin significantly limited serum corticosterone elevation related to restraint stress (p < .05). Restraint stress aggravated alveolar bone loss in rats with periodontitis, while systemic melatonin administration significantly reduced stress-related periodontal bone loss. According to the biochemical analyses, melatonin significantly lowered IL-1ß/IL-10, OSI (TOS/TAS), and RANKL/OPG rates, which were significantly elevated in the S-Ep group. CONCLUSION: Melatonin can significantly prevent the limited destructive effects of stress on periodontal tissues by suppressing RANKL-related osteoclastogenesis and oxidative stress.
Assuntos
Perda do Osso Alveolar , Melatonina , Periodontite , Ratos Sprague-Dawley , Estresse Psicológico , Animais , Melatonina/uso terapêutico , Melatonina/farmacologia , Periodontite/prevenção & controle , Periodontite/tratamento farmacológico , Estresse Psicológico/complicações , Masculino , Ratos , Perda do Osso Alveolar/prevenção & controle , Antioxidantes/uso terapêutico , Antioxidantes/farmacologia , Modelos Animais de Doenças , Ligante RANK , Estresse Oxidativo/efeitos dos fármacos , Distribuição Aleatória , Restrição Física , Osteoprotegerina/análiseRESUMO
BACKGROUND AND OBJECTIVE: Osteoporosis is associated with bone microarchitecture alterations, and the depletion of estrogen during menopause is a major contributing factor to its development. The literature highlights the noteworthy role of gut microbiota in bone metabolism, particularly in the progression of osteoporosis. Periodontal disease leads to alveolar bone loss, which may be influenced by estrogen deficiency, and this mechanism is intricately associated with an imbalance in systemic microbiota. The aim of this study was to evaluate the effects of Bifidobacterium animalis subsp. lactis HN019 (B. lactis HN019) and Lacticaseibacillus casei 01 (L. casei 01) administrations on an osteoporosis animal model. MATERIALS AND METHODS: Thirty-three female rats were randomly divided into three groups: control (C-OVX), C-OVX-HN019 and C-OVX-LC01. All animals were ovariectomized. In groups C-OVX-HN019 and C-OVX-LC01, the probiotics were administered for 4 months. All animals were euthanized after 16 weeks from ovariectomy. Microtomographic, histopathological and immunohistochemical examinations were conducted on periodontal tissues, whereas histomorphometry, histopathological and immunohistochemical analyses were carried out on the intestine. The levels of estradiol were assessed in blood using an immunoenzymatic assay. The data were subjected to statistical analyses (p < .05). RESULTS: The C-OVX-LC01 group exhibited a significant reduction in alveolar bone porosity and an increase in connective tissue density compared to C-OVX (p < .05). The C-OVX-HN019 and C-OVX-LC01 groups presented reduced expression of TRAP and RANKL compared to the C-OVX (p < .05). The C-OVX group presented villi defects, mild neutrophil infiltration, decrease in both villous height and intestinal crypts and reduced expression of intestinal junctional epithelium markers e-cadherin and claudin 01 compared to C-OVX-HN019 and C-OVX-LC01 (p < .05). The C-OVX group had lower estradiol levels than C-OVX-HN019 and C-OVX-LC01 (p < .05). CONCLUSION: The probiotic therapy promoted a reduction in alveolar bone destruction and intestinal permeability as well as an increase in estradiol levels in ovariectomized rats. Specifically, the probiotic strain Lacticaseibacillus casei 01 exhibited greater effectiveness compared to Bifidobacterium animalis subsp. lactis HN019, indicating strain-dependent outcomes.
Assuntos
Estradiol , Osteoporose , Ovariectomia , Probióticos , Animais , Estradiol/sangue , Probióticos/uso terapêutico , Probióticos/farmacologia , Feminino , Ratos , Osteoporose/patologia , Perda do Osso Alveolar/patologia , Perda do Osso Alveolar/prevenção & controle , Modelos Animais de Doenças , Lacticaseibacillus casei , Bifidobacterium animalis , Microtomografia por Raio-X , Processo Alveolar/patologia , Intestinos/patologia , Intestinos/microbiologia , Microbioma Gastrointestinal , Ratos WistarRESUMO
OBJECTIVE: This study aimed to evaluate the regenerative capacities of octacalcium phosphate collagen composite (OCP/Col) in one-wall intrabony defects in dogs. The background data discuss the present state of the field: No study has assessed the efficacy of OCP/Col for periodontal regeneration therapy despite the fact that OCP/Col has proved to be efficient for bone regeneration. METHODS: In six beagle dogs, the mandibular left third premolars were extracted 12 weeks before the experimental surgery. Standardized bone defects (5 mm in height and 4 mm in width) were simulated on the distal surface of the second premolars and mesially on the fourth premolars. The defect was filled with either OCP/Col (experimental group) or left empty (control group). Histological and histomorphometric characteristics were compared 8 weeks after surgery. RESULTS: No infectious or ankylotic complications were detected at any of the tested sites. The experimental group exhibited a significantly greater volume, height, and area of newly formed bone than the control group. The former also showed a greater height of the newly formed cementum than the latter, although the results were not statistically significant. The newly formed periodontal ligaments were inserted into newly formed bone and cementum in the experimental group. CONCLUSION: OCP/Col demonstrated high efficacy for bone and periodontal tissue regeneration that can be successfully applied for one-wall intrabony defects.
Assuntos
Regeneração Óssea , Fosfatos de Cálcio , Colágeno , Animais , Cães , Fosfatos de Cálcio/uso terapêutico , Regeneração Óssea/efeitos dos fármacos , Colágeno/uso terapêutico , Perda do Osso Alveolar/cirurgia , Ligamento Periodontal/patologia , Substitutos Ósseos/uso terapêutico , Regeneração Tecidual Guiada Periodontal/métodos , Masculino , Mandíbula/cirurgia , Cemento Dentário/patologiaRESUMO
OBJECTIVE: The study aimed to investigate the change of amyloid precursor protein (APP) processing and amyloid ß (Aß) metabolites in linking periodontitis to Alzheimer's disease (AD). BACKGROUND: Aß is one of the main pathological features of AD, and few studies have discussed changes in its expression in peripheral tissues or analyzed the relationship between the peripheral imbalance of Aß production and clearance. METHODS: A murine model of periodontitis was established by oral infection with Porphyromonas gingivalis (P. gingivalis). Micro-computed tomography (Micro-CT) was used to observe the destruction of the alveolar bone. Nested quantitative polymerase chain reaction (qPCR) was used to measure small quantities of P.gingivalis DNA in different tissues. Behavioral experiments were performed to measure cognitive function in the mice. The mRNA levels of TNF-α, IL-6, IL-8, RANKL, OPG, APP695, APP751, APP770, and BACE1 in the gingival tissues or cortex were detected by RT-PCR. The levels of Aß1-40 and Aß1-42 in gingival crevicular fluid (GCF) and plasma were tested by ELISA. RESULTS: P. gingivalis oral infection was found to cause alveolar bone resorption and impaired learning and memory. P.gingivalis DNA was detected in the gingiva, blood and cortex of the P.gingivalis group by nested qPCR (p < .05). The mRNA expression of TNF-α, IL-6, IL-8, RANKL/OPG, and BACE1 in the gingival tissue was significantly higher than that in the control group (p < .05). Similarly, upregulated mRNA levels of APP695 and APP770 were observed in the gingival tissuses and cortex of the P. gingivalis group (p < .05). The levels of Aß1-40 and Aß1-42 in the GCF and plasma of the P. gingivalis group were significantly higher than those in the control group (p < .05). CONCLUSION: P. gingivalis can directly invade the brain via hematogenous infection. The invasion of P. gingivalis could trigger an immune response and lead to an imbalance between Aß production and clearance in peripheral tissues, which may trigger an abnormal Aß metabolite in the brain, resulting in the occurrence and development of AD.
Assuntos
Perda do Osso Alveolar , Periodontite , Camundongos , Animais , Precursor de Proteína beta-Amiloide/genética , Porphyromonas gingivalis/metabolismo , Secretases da Proteína Precursora do Amiloide , Peptídeos beta-Amiloides/metabolismo , Fator de Necrose Tumoral alfa , Modelos Animais de Doenças , Microtomografia por Raio-X , Interleucina-6 , Interleucina-8 , Ácido Aspártico Endopeptidases , Periodontite/metabolismo , RNA Mensageiro/análise , DNARESUMO
OBJECTIVE: This study aimed to investigate the factors influencing the clinical outcomes of regenerative therapy using recombinant human fibroblast growth factor-2 (rhFGF-2). BACKGROUND: rhFGF-2 promotes periodontal regeneration, and identifying the factors influencing this regeneration is important for optimizing the effectiveness of rhFGF-2. METHODS AND MATERIALS: This study used a hospital information-integrated database to identify patients who underwent periodontal regenerative therapy with rhFGF-2. Factors included age, smoking status, diabetes mellitus (DM), periodontal inflamed surface area (PISA) at the initial visit, whether the most posterior tooth was involved or not, and preoperative radiological bone defect angle. Periodontal regenerative therapy outcomes were defined as good if radiographic bone fill ≥35% or periodontal pocket closure at 9-15 months after surgery. Bone fill rate (%) and periodontal pocket depth (mm) were also used as outcome measures. Factors were evaluated by simple regression analysis, and then the association between factors and the outcomes was determined by multivariate analysis. RESULTS: PISA and age at the first visit did not significantly influence the success or failure of bone fill rate byrhFGF-2. However, DM, radiographic bone defect angle, and the most posterior tooth significantly influenced the regenerative effect (success/failure in bone fill) of rhFGF-2. The most posterior tooth was significantly associated with bone fill rate by rhFGF-2. Examination of the association between pocket closure and factors shows that the most posterior tooth significantly influenced. The most posterior tooth and preoperative PPD were significantly associated with pocket reduction depth. For the most posterior tooth, a significantly higher bone regeneration rate (p < .05) was observed with a combination of autologous bone graft and rhFGF-2 than with rhFGF-2 alone, and the effect was significant in multivariate analysis. CONCLUSIONS: The radiographic bone defect angle, the involvement of most posterior teeth, and the presence of DM influenced the effectiveness of rhFGF-2 in periodontal regeneration. However, PISA values and age at the initial visit had no significant effect.
Assuntos
Fator 2 de Crescimento de Fibroblastos , Regeneração Tecidual Guiada Periodontal , Proteínas Recombinantes , Humanos , Masculino , Fator 2 de Crescimento de Fibroblastos/uso terapêutico , Fator 2 de Crescimento de Fibroblastos/farmacologia , Pessoa de Meia-Idade , Feminino , Estudos de Casos e Controles , Regeneração Tecidual Guiada Periodontal/métodos , Proteínas Recombinantes/uso terapêutico , Proteínas Recombinantes/farmacologia , Resultado do Tratamento , Adulto , Idoso , Regeneração Óssea/efeitos dos fármacos , Perda do Osso Alveolar/diagnóstico por imagemRESUMO
OBJECTIVE: This study aims to investigate the mechanisms underlying the impaired healing response by diabetes after periodontal therapy. BACKGROUND: Outcomes of periodontal therapy in patients with diabetes are impaired compared with those in patients without diabetes. However, the mechanisms underlying impaired healing response to periodontal therapy have not been sufficiently investigated. MATERIALS AND METHODS: Zucker diabetic fatty (ZDF) and lean (ZL) rats underwent experimental periodontitis by ligating the mandibular molars for one week. The gingiva at the ligated sites was harvested one day after ligature removal, and gene expression was comprehensively analyzed using RNA-Seq. In patients with and without type 2 diabetes (T2D), the corresponding gene expression was quantified in the gingiva of the shallow sulcus and residual periodontal pocket after non-surgical periodontal therapy. RESULTS: Ligation-induced bone resorption and its recovery after ligature removal were significantly impaired in the ZDF group than in the ZL group. The RNA-Seq analysis revealed 252 differentially expressed genes. Pathway analysis demonstrated the enrichment of downregulated genes involved in the peroxisome proliferator-activated receptor (PPAR) signaling pathway. PPARα and PPARγ were decreased in mRNA level and immunohistochemistry in the ZDF group than in the ZL group. In clinical, probing depth reduction was significantly less in the T2D group than control. Significantly downregulated expression of PPARα and PPARγ were detected in the residual periodontal pocket of the T2D group compared with those of the control group, but not in the shallow sulcus between the groups. CONCLUSIONS: Downregulated PPAR subtypes expression may involve the impaired healing of periodontal tissues by diabetes.
Assuntos
Diabetes Mellitus Tipo 2 , Periodontite , Ratos Zucker , Cicatrização , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/genética , Animais , Ratos , Periodontite/terapia , Periodontite/genética , Cicatrização/genética , Masculino , Humanos , Gengiva/metabolismo , PPAR gama/genética , PPAR gama/metabolismo , PPAR alfa/genética , PPAR alfa/metabolismo , Perda do Osso Alveolar/terapia , Modelos Animais de Doenças , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/terapia , Pessoa de Meia-IdadeRESUMO
OBJECTIVE: The purpose of this study is to investigate regenerative process by immunohistochemical analysis and evaluate periodontal tissue regeneration following a topical application of BDNF to inflamed 3-wall intra-bony defects. BACKGROUND: Brain-derived neurotrophic factor (BDNF) plays a role in the survival and differentiation of central and peripheral neurons. BDNF can regulate the functions of non-neural cells, osteoblasts, periodontal ligament cells, endothelial cells, as well as neural cells. Our previous study showed that a topical application of BDNF enhances periodontal tissue regeneration in experimental periodontal defects of dog and that BDNF stimulates the expression of bone (cementum)-related proteins and proliferation of human periodontal ligament cells. METHODS: Six weeks after extraction of mandibular first and third premolars, 3-wall intra-bony defects were created in mandibular second and fourth premolars of beagle dogs. Impression material was placed in all of the artificial defects to induce inflammation. Two weeks after the first operation, BDNF (25 and 50 µg/mL) immersed into atelocollagen sponge was applied to the defects. As a control, only atelocollagen sponge immersed in saline was applied. Two and four weeks after the BDNF application, morphometric analysis was performed. Localizations of osteopontin (OPN) and proliferating cell nuclear antigen (PCNA)-positive cells were evaluated by immunohistochemical analysis. RESULTS: Two weeks after application of BDNF, periodontal tissue was partially regenerated. Immunohistochemical analyses revealed that cells on the denuded root surface were positive with OPN and PCNA. PCNA-positive cells were also detected in the soft connective tissue of regenerating periodontal tissue. Four weeks after application of BDNF, the periodontal defects were regenerated with cementum, periodontal ligament, and alveolar bone. Along the root surface, abundant OPN-positive cells were observed. Morphometric analyses revealed that percentage of new cementum length and percentage of new bone area of experimental groups were higher than control group and dose-dependently increased. CONCLUSION: These findings suggest that BDNF could induce cementum regeneration in early regenerative phase by stimulating proliferation of periodontal ligament cells and differentiation into periodontal tissue cells, resulting in enhancement of periodontal tissue regeneration in inflamed 3-wall intra-bony defects.
Assuntos
Perda do Osso Alveolar , Fator Neurotrófico Derivado do Encéfalo , Cementogênese , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Fator Neurotrófico Derivado do Encéfalo/uso terapêutico , Cães , Cementogênese/efeitos dos fármacos , Antígeno Nuclear de Célula em Proliferação/metabolismo , Osteopontina , Ligamento Periodontal/patologia , Ligamento Periodontal/efeitos dos fármacos , Masculino , Regeneração Tecidual Guiada Periodontal/métodos , Regeneração Óssea/efeitos dos fármacos , Cemento Dentário/patologia , Cemento Dentário/efeitos dos fármacos , Periodonto/patologia , Periodonto/metabolismo , Mandíbula , Proliferação de Células/efeitos dos fármacosRESUMO
Periodontitis, the second most common oral disease, is primarily initiated by inflammatory responses and osteoclast differentiation, in which the MAPK signaling pathway and mitochondrial function play important roles. 3-methyl-1H-indol-1-yl dimethylcarbamodithioate (3o), a hybrid of indole and dithiocarbamate, was first synthesized by our group. It has shown anti-inflammatory activity against lipopolysaccharide-induced acute lung injury. However, it is not known if 3o can exert effects in periodontitis. In vitro study: LPS-induced macrophage inflammation initiation and a receptor activator of nuclear factor κB ligand-stimulated osteoclast differentiation model were established. Cell viability, inflammatory cytokines, osteoclast differentiation, the MAPK signaling pathway, and mitochondrial function before and after treatment with 3o were investigated. In vivo study: Alveolar bone resorption, inflammatory cytokine expression, osteoclast differentiation, and the underlying mechanisms were assessed in mice with periodontitis. Inflammatory cytokine expression and osteoclast differentiation appeared downregulated after 3o treatment. 3o inhibited the MAPK signaling pathway and restored mitochondrial function, including mitochondrial reactive oxygen species, mitochondrial membrane potential, and ATP production. Meanwhile, 3o reduced inflammation activation and bone resorption in mice with periodontitis, reflected by the decreased expression of inflammatory cytokines and osteoclasts, implying that 3o inhibited the MAPK signaling pathway and the mitochondrial oxidative DNA damage marker 8-OHdG. These results highlight the protective role of 3o in periodontitis in mice and reveal an important strategy for preventing periodontitis.
Assuntos
Indóis , Sistema de Sinalização das MAP Quinases , Mitocôndrias , Osteoclastos , Periodontite , Animais , Mitocôndrias/efeitos dos fármacos , Periodontite/tratamento farmacológico , Camundongos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Osteoclastos/efeitos dos fármacos , Indóis/farmacologia , Indóis/uso terapêutico , Diferenciação Celular/efeitos dos fármacos , Citocinas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Perda do Osso Alveolar/tratamento farmacológico , Camundongos Endogâmicos C57BL , Células RAW 264.7RESUMO
BACKGROUND AND OBJECTIVE: Prevention of periodontal bone resorption triggered by Porphyromonas gingivalis (P. gingivalis) is crucial for dental stability. Capsaicin, known as the pungent ingredient of chili peppers, can activate key signaling molecules involved in osteogenic process. However, the effect of capsaicin on osteogenesis of periodontal ligament stem cells (PDLSCs) under inflammation remains elusive. METHODS: P. gingivalis culture suspension was added to mimic the inflammatory status after capsaicin pretreatment. The effects of capsaicin on the osteogenesis of PDLSCs, as well as mitochondrial morphology, Ca2+ level, reactive oxygen species (ROS), mitochondrial membrane potential (MMP), and osteogenesis-regulated protein expression levels were analyzed. Furthermore, a mouse experimental periodontitis model was established to evaluate the effect of capsaicin on alveolar bone resorption and the expression of osteogenesis-related proteins. RESULTS: Under P. gingivalis stimulation, capsaicin increased osteogenesis of PDLSCs. Not surprisingly, capsaicin rescued the damage to mitochondrial morphology, decreased the concentration of intracellular Ca2+ and ROS, enhanced MMP and activated phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway. The in vivo results showed that capsaicin significantly attenuated alveolar bone loss and augmented the expression of bone associated proteins. CONCLUSION: Capsaicin increases osteogenesis of PDLSCs under inflammation and reduces alveolar bone resorption in mouse experimental periodontitis.
Assuntos
Capsaicina , Mitocôndrias , Osteogênese , Ligamento Periodontal , Porphyromonas gingivalis , Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais , Células-Tronco , Serina-Treonina Quinases TOR , Ligamento Periodontal/citologia , Ligamento Periodontal/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Animais , Células-Tronco/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Capsaicina/farmacologia , Serina-Treonina Quinases TOR/metabolismo , Camundongos , Transdução de Sinais/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Humanos , Espécies Reativas de Oxigênio/metabolismo , Perda do Osso Alveolar/prevenção & controle , Periodontite/microbiologia , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Células Cultivadas , Modelos Animais de DoençasRESUMO
AIM: To compare the clinical and radiographic outcomes of flapless procedure alone or in combination with enamel matrix derivatives (EMD) in the treatment of deep intrabony defects. MATERIALS AND METHODS: Forty-six patients re-evaluated after non-surgical therapy were randomly assigned to the test (flapless with EMD) or control group (flapless alone). Clinical measurements were recorded pre-surgery and at 6 and 12 months after surgery, and radiographic measurements were taken pre-surgery and after 12 months. RESULTS: Forty-six patients completed the study. Improvements were observed in both groups at 12 months for mean clinical attachment level (CAL) gain, with significant differences between test (3.9 ± 1.1 mm) and control groups (3.0 ± 1.2) (p = .017). Probing pocket depth (PPD) reduction (4.0 ± 0.7 vs. 3.3 ± 1.4 mm) was also near to statistical significance (p = .051). Also, more sites achieved successful composite outcome measure (final PPD ≤ 4 mm and CAL gain ≥3 mm) for the regenerative treatment in the flapless + EMD group (82.6% vs. 52.2%; p = .028). In terms of radiographic outcomes, EMD yielded a greater defect bone fill than flapless treatment alone (3.0 ± 1.0 mm vs. 1.8 ± 1.5 mm; p < .001). CONCLUSIONS: The additional application of EMD during the flapless procedure for intrabony defects slightly improved clinical and radiographic outcomes. CLINICALTRIALS: gov identification number: NCT05456555.
Assuntos
Perda do Osso Alveolar , Proteínas do Esmalte Dentário , Humanos , Masculino , Feminino , Perda do Osso Alveolar/cirurgia , Perda do Osso Alveolar/diagnóstico por imagem , Perda do Osso Alveolar/terapia , Pessoa de Meia-Idade , Proteínas do Esmalte Dentário/uso terapêutico , Resultado do Tratamento , Adulto , Regeneração Tecidual Guiada Periodontal/métodosRESUMO
AIM: To assess the potential benefits of minimally invasive non-surgical therapy (MINST) in teeth with intrabony defects and to explore factors associated with the outcomes. MATERIALS AND METHODS: A multi-centre trial was conducted in 100 intrabony defects in periodontitis patients in private practice. Steps 1 and 2 periodontal therapy including MINST were provided. Clinical and radiographic data were analysed at baseline and 12 months after treatment, with the primary aim being change in radiographic defect depth at 12 months. RESULTS: Eighty-four patients completed the 12-month follow up. The mean total radiographic defect depth reduced by 1.42 mm and the defect angle increased by 3° (both p < .05). Statistically significant improvements in probing pocket depth (PPD) and clinical attachment level (CAL) were seen at 12 months compared to baseline (p < .001). Fifty-six defects (66.7%) achieved pocket closure (PPD ≤ 4 mm) and 49 defects (58.3%) achieved the composite outcome (PPD ≤ 4 mm and CAL gain ≥3 mm). Deeper and narrower angled defects were positively correlated with radiographic and clinical improvements, respectively. CONCLUSIONS: Improvements in clinical and radiographic outcomes were seen after MINST. This study highlights the generalizability and wide applicability of this approach, further supporting its effectiveness in the treatment of intrabony defects. CLINICAL TRIAL REGISTRATION: NCT03741374. https://clinicaltrials.gov/study/NCT03741374?cond=minimally%20invasive%20non%20surgical%20therapy&locStr=UK&country=United%20Kingdom&distance=50&rank=2.
Assuntos
Perda do Osso Alveolar , Humanos , Masculino , Feminino , Estudos Prospectivos , Pessoa de Meia-Idade , Perda do Osso Alveolar/terapia , Perda do Osso Alveolar/diagnóstico por imagem , Perda do Osso Alveolar/cirurgia , Adulto , Resultado do Tratamento , Idoso , Periodontite/terapia , Periodontite/cirurgiaRESUMO
AIM: To systematically identify, synthesize and critically summarize the available scientific evidence from randomized controlled trials (RCTs) regarding whether short (≤6 mm) perform as well as long (≥10 mm) implants regarding implant survival, marginal bone loss, and biologic and prosthetic complications in different clinical scenarios. MATERIALS AND METHODS: Cochrane Collaboration's risk of bias tool and the GRADE approach were applied. Results were synthesized using random-effects meta-analyses assessed by trial sequential analyses. RESULTS: Forty reports on 19 RCTs comprising 2214 (1097 short; 1117 long) implants were included. Moderate/high certainty/quality evidence demonstrated similar 5-year survival rates for ≤6-mm and ≥10-mm implants in non-augmented bone and full-mouth rehabilitation in either jaw, and for 6-mm implants in the maxilla instead of sinus lift. Nevertheless, the evidence for 5-year survival rates remains inconclusive or insufficient for the remaining combinations of implant lengths and clinical scenarios. They include 4-mm and 5-mm implants as alternatives to sinus lift as well as placing all implant lengths ≤6 mm instead of vertical ridge augmentation with long implants. Marginal bone level and short- and long-term biologic or prosthetic complications were similar. CONCLUSIONS: Based on moderate/high certainty/quality evidence from 5-year RCTs, implants ≤6 mm may be viable alternatives to ≥10-mm implants in either jaw in native bone and full-arch rehabilitation, and 6-mm implants may be used as an alternative to sinus lift. TRIAL REGISTRATION: PROSPERO ID: CRD42021254365.