Study on the mechanism of curcumin in the treatment of periodontitis through network pharmacology and mole-cular docking / 华西口腔医学杂志

OBJECTIVES@#This study aims to explore the therapeutic targets of curcumin in periodontitis through network pharmacology and molecular docking technology.@*METHODS@#Targets of curcumin and periodontitis were predicted by different databases, and the protein-protein interaction (PPI) network constructed by String revealed the interaction between curcumin and periodontitis. The key target genes were screened for Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. Molecular docking was performed to analyze the binding potential of curcumin to periodontitis.@*RESULTS@#A total of 672 periodontitis-related disease targets and 107 curcumin-acting targets were obtained from the databases, and 20 key targets were screened. The GO and KEGG analyses of the 20 targets showed that curcumin might play a therapeutic role through the hypoxia-inducible factor (HIF)-1 and parathyroid hormone (PTH) signaling pathways. Molecular docking analysis showed that curcumin had good binding potential with multiple targets.@*CONCLUSIONS@#The potential key targets and molecular mechanisms of curcumin in treating periodontitis provide a theoretical basis for new drug development and clinical applications.

CD301b+ macrophage: the new booster for activating bone regeneration in periodontitis treatment / 国际口腔科学杂志·英文版

Periodontal bone regeneration is a major challenge in the treatment of periodontitis. Currently the main obstacle is the difficulty of restoring the regenerative vitality of periodontal osteoblast lineages suppressed by inflammation, via conventional treatment. CD301b+ macrophages were recently identified as a subpopulation that is characteristic of a regenerative environment, but their role in periodontal bone repair has not been reported. The current study indicates that CD301b+ macrophages may be a constituent component of periodontal bone repair, and that they are devoted to bone formation in the resolving phase of periodontitis. Transcriptome sequencing suggested that CD301b+ macrophages could positively regulate osteogenesis-related processes. In vitro, CD301b+ macrophages could be induced by interleukin 4 (IL-4) unless proinflammatory cytokines such as interleukin 1β (IL-1β) and tumor necrosis factor α (TNF-α) were present. Mechanistically, CD301b+ macrophages promoted osteoblast differentiation via insulin-like growth factor 1 (IGF-1)/thymoma viral proto-oncogene 1 (Akt)/mammalian target of rapamycin (mTOR) signaling. An osteogenic inducible nano-capsule (OINC) consisting of a gold nanocage loaded with IL-4 as the "core" and mouse neutrophil membrane as the "shell" was designed. When injected into periodontal tissue, OINCs first absorbed proinflammatory cytokines in inflamed periodontal tissue, then released IL-4 controlled by far-red irradiation. These events collectively promoted CD301b+ macrophage enrichment, which further boosted periodontal bone regeneration. The current study highlights the osteoinductive role of CD301b+ macrophages, and suggests a CD301b+ macrophage-targeted induction strategy based on biomimetic nano-capsules for improved therapeutic efficacy, which may also provide a potential therapeutic target and strategy for other inflammatory bone diseases.

Resistencia antimicrobiana de Porphyromonas gingivalis periodontopatógena en una población uruguaya / Antimicrobial resistance of periodontopathogenic Porphyromonas gingivalis in a Uruguayan population

La periodontitis afecta en Uruguay a más de 340 mil individuos. Para optimizar su tratamiento además del mantenimiento profesional de la salud periodontal, del control de placa por el paciente, y del control de otros factores de riesgo como las enfermedades sistémicas, estrés, hábito tabáquico y susceptibilidad genética, se administran frecuentemente antibióticos como coadyuvantes. Entre los periodontopatógenos más prevalentes Porphyromonas gingivalis es el más estudiado a nivel molecular, pero se encontró poca información para la región acerca de su sensibilidad a los antibióticos. Dado el compromiso etiológico en la enfermedad periodontal de Porphyromonas gingivalis, es relevante la determinación de su resistencia antimicrobiana in vitro para un tratamiento racional considerando la temporalidad de los resultados. Objetivo general: Contribuir al conocimiento de la infección por Porphyromonas gingivalis y al uso racional de antibióticos en el tratamiento de la periodontitis. Objetivos específicos: caracterizar la población estudiada según factores de riesgo modificables y no modificables para periodontitis, cultivar e identificar Porphyromonas gingivalis de la bolsa periodontal de la población, determinar la concentración inhibitoria mínima (CIM) a los antibióticos y la producción de betalactamasa, analizar las concentraciones en el fluido gingival y su relación con la CIM, establecer la relación riesgo -beneficio- costo de los diferentes tratamientos antibióticos. Métodos: se realizó la toma de muestras de la microbiota del surco gingival a los pacientes que reunieron los criterios de inclusión y firmaron consentimiento informado.Las muestras se incubaron en diferentes medios microbiológicos específicos, para identificar el microorganismo diana, determinar su sensibilidad a la amoxicilina, asociación amoxicilina ­ ácido clavulánico, metronidazol, tetraciclina, clindamicina, ciprofoxacina y moxifloxacina. Resultados: de un total de 29 pacientes en un rango de 23 a 78 años y con bolsas periodontales iguales o mayores a 4 mm, se obtuvieron 12 aislamientos de Porphyromonas gingivalis. Estos aislamientos se realizaron en pacientes que tenían bolsas periodontales con una profundidad mayor a 4 mm, con una edad comprendida entre 41 a 70 años. Si bien el 48% de la población era fumadora, sólo el 29% presentó aislamientos. Todos los pacientes diabéticos presentaron Porphyromonas gingivalis. Los 12 aislamientos fueron betalactamasa positivos y por lo tanto resistentes a las penicilinas G y V, aminopenicilinas, amoxipenicilinas, ureidopenicilinas y carboxipenicilinas. El rango de CIM fue: amoxicilina de 8-16 mg.L-1, asociación amoxicilina ­ ácido clavulánico 0.25/0.125-1/0.5 mg.L-1, metronidazol de 0,25- 1 mg.L-1, tetraciclina 0.25-0.5 mg.L-1, clindamicina 0.25-0.5 mg.L-1, ciprofloxacina de 1-2 mg.L-1y moxifloxacina 0.064-0.25 mg.L-1. El parámetro farmacocinética/farmacodinamia (PK/PD) en el fluido gingival indica actividades antimicrobianas insuficientes para amoxicilina-ácido clavulánico y satisfactoria para el resto de los antibióticos a los que la bacteria es sensible in vitro. En orden decreciente, la mejor relación riesgo-beneficio-costo fue para el metronidazol seguido de clindamicina, la moxifloxacina y la tetraciclina. Conclusiones: el metronidazol y clindamicina podrían ser los más beneficiosos como coadyuvantes para la disminución de la carga del periodonto patógeno en el fluido crevicular. En segundo lugar podrían usarse tetraciclina y moxifloxacina debido a su menor seguridad.Este es el primer estudio nacional que aporta datos sobre proporción de Porphyromonas gingivalis en periodontitis por método de cultivo, de su sensibilidad in vitro a los antimicrobianos y de la actividad antimicrobiana de estos últimos en el fluido crevicular.

Efectos de la administración local de PTH 1-34 a bajas dosis en un modelo experimental de periodontitis: estudio piloto / Local effects of low dose of PTH 1-34 on experimental periodontitis: pilot study

La periodontitis es una patología inflamatoria que aumenta la resorción de hueso alveolar (HA), pérdida de la inserción dentaria y posible exfoliación. Evaluamos el efecto de la administración intermitente de bajas dosis de parathormona (PTH) 1-34 sobre la recuperación de la masa ósea pérdida en un modelo experimental de periodontitis inducida por una ligadura periodontal (LP) con hilo de algodón alrededor de la pieza dentaria. Las ratas fueron divididas luego de 5 días en instaurada la periodontitis en: CT LP sin trata-miento y PTH LP tratados con 0,2 µg/kg PTH 1-34 subcutánea local, tres veces por semana por 17 días. El control absoluto fue un tercer grupo sin LP (CT). Se estudiaron parámetros antropométricos, bioquímicos e histomosfométricos en tibias y hemimandibulas. La calcemia, fosfatemia, CTX sérico, PTHi y vo-lumen óseo (BV/TV%) de tibias fueron similares en los tres grupos. El BV/TV% del HA fue significativamente menor en PTH LP respecto de CT pero mayor que CT LP (p<0.05). La pérdida ósea de HA porcentual fue significativamente mayor en CT LP (p<0.05). La altura del ligamento periodontal fue significativamente menor en PTH LP que en CT (p<0.05) y mayor respecto de CT LP, sin alcanzar diferencias significativas. Los resultados del presente estudio piloto sugieren que la administración intermitente de PTH en bajas dosis y durante un periodo de tiempo corto disminuye la progresión de la enfermedad periodontal sin generar efectos sistémicos. Como no se logró regenerar totalmente el tejido periodontal se requieren estudios adicionales. (AU)

Periodontitis is an inflammatory chronic disease with high prevalence in adults that induces a progressive alveolar bone (AB) loss leading to tooth loss. Experimental periodontitis can be induced in rats by cotton ligature placement (LP) in the gingival sulcus around the molar teeth. The biofilm accumulation and disruption of the gingival epithelium lead to bone resorption. We investigated whether intermittent administration of a low dose of PTH 1-34 may recover the alveolar bone loss in the experimental periodontitis induced in female Wistar rats. Animals were randomly divided in two groups which were subcutaneously injected with: saline solution (CT LP) or 0,2 µg/kg PTH 1-34 (PTH LP) three times per week during 17 days. Unligated rats were taken as healthy controls (CT). Anthropometric, biochemical and histologic analysis of tibia and hemimandible were done. No differences in serum calcium, phosphorus, CTX, PTHi or subchondral tibia bone volume (BV/TV%) were observed between the three groups. AB BV/TV% was significantly lower in PTH LP than in CT but higher than in CT LP (p<0.05). The highest percentage of AB loss was observed in CT LP. The height of periodontal ligament was lower in PTH LP than in CT (p<0.05) but not significantly higher than CT LP.The increase in AB loss by experimental periodontitis appears to be corrected by the intermittent administration of low doses of PTH without systemic effect. As the recovery of periodontal tissue was only partial, additional studies should be done.

Estrés oxidativo en saliva generado por el humo de tabaco: impacto en la periodontitis y perspectivas hacia el uso de farmacología redox / Oxidative stress in saliva induced by tobacco smoke: impact on periodontitis and perspectives with redox pharmacology / Estresse oxidativo na saliva gerado pela fumaça do tabaco: impacto na periodontite e perspectivas para o uso da farmacologia redox

Numerosos reportes demuestran la presencia de biomarcadores de estrés oxidativo en la saliva de fumadores y hay un creciente interés en correlacionar estos procesos moleculares con la etiología de algunas enfermedades orales, como la periodontitis, una enfermedad inmunoinflamatoria crónica relacionada con un desequilibrio de la homeostasis redox celular. Objetivo: realizar una revisión narrativa sobre la relación entre la disminución de la capacidad antioxidante salival inducida por humo de tabaco, la periodontitis y el potencial uso de farmacología redox para el tratamiento de esta patología. Métodos: se realizó una búsqueda bibliográfica en bases de datos como PUBMED (NLM, NIH, NCBI) y SciELO. Resultados: existe evidencia que relaciona la baja capacidad antioxidante salival con un retraso en el restablecimiento de las condiciones normales en la cavidad oral ante el desarrollo de periodontitis. A su vez, el estado inflamatorio asociado colabora sinérgicamente, provocando un mayor daño tisular con pérdida de tejidos de soporte dentario, fenómeno que podría ser modulado por la acción de farmacología redox. Conclusiones: la intervención con farmacología redox, podría atenuar los biomarcadores de progresión de la enfermedad periodontal, constituyendo una herramienta prometedora para utilizar en conjunto con las estrategias de tratamiento tradicionales.

Numerous reports demonstrate the presence of oxidative stress biomarkers in the saliva of smokers and there is a growing interest in correlating these molecular processes with the etiology of some oral diseases, such as periodontitis, a chronic immunoinlammatory disease related to an imbalance of cellular redox homeostasis. Aims: achieve a narrative review on the relationship between the decrease in salivary antioxidant capacity induced by tobacco smoke, periodontitis, and the potential use of redox pharmacology for the treatment of this pathology. Methods: a bibliographic search was carried out in databases such as PUBMED (NLM, NIH, NCBI) and SciELO. Results: there is evidence that relates the low salivary antioxidant capacity with a delay in the reestablishment of normal conditions in the oral cavity before the development of periodontitis. In turn, the associated inflammatory state collaborates synergistically, causing greater tissue damage with loss of dental support tissues, a phenomenon that could be modulated by the action of redox pharmacology. Conclusions: intervention with redox pharmacology could attenuate the biomarkers of periodontal disease progression, constituting a promising tool to be used in conjunction with traditional treatment strategies.

Muitos artigos demonstram a presença de biomarcadores de estresse oxidativo na saliva de fumantes e há um interesse crescente em correlacionar esses processos moleculares com a etiologia de algumas doenças bucais, como a periodontite, uma doença imunoinlamatória crônica relacionada a um desequilíbrio da redox celular homeostase. Objetivo: realizar uma revisão narrativa sobre a relaçã o entre a diminuiçã o da capacidade antioxidante salivar induzida pela fumaça do tabaco, periodontite e o uso potencial da farmacologia redox para o tratamento desta patologia. Métodos: uma pesquisa bibliográica foi realizada usando bases de dados como PUBMED (NLM, NIH, NCBI) e SciELO. Resultados: há evidências que relacionam a baixa capacidade antioxidante salivar com o retardo no restabelecimento das condições normais da cavidade oral antes do desenvolvimento da periodontite. Por sua vez, o estado inflamatório associado colabora sinergicamente, causando maior dano tecidual com perda de tecidos de suporte dentário, fenômeno que poderia ser modulado pela açã o da farmacologia redox. Conclusões: a intervençã o com a farmacologia redox poderia atenuar os biomarcadores de progressã o da doença periodontal, constituindo-se em uma ferramenta promissora para ser utilizada em conjunto com estratégias tradicionais de tratamento.

Vigilancia clínica-microbiológica de una Periodontitis Grado C etapa III en cinco años / Clinical-microbiological vigilance of a C Grade Periodontitis Stage III in five years

Resumen Introducción: Diversas técnicas se utilizan para tratar y mantener los dientes afectados con Periodontitis de estadio III grado C, sin embargo, hay poca información sobre cómo se modifican los parámetros clínicos periodontales y la composición microbiológica durante el tratamiento convencional y quirúrgico. Objetivo: Evaluar la respuesta clínica y microbiológica en una paciente con periodontitis estadio III grado C generalizada durante 5 años. Cuyo tratamiento consistió en terapia periodontal no quirúrgica y quirúrgica utilizando material regenerativo y sustituto óseo. Metodología: Se realizó raspado y alisado radicular progresivo, combinado con antibióticos y cirugía en sitios con defectos infraóseos. Se tomó registro de placa bacteriana subgingival (PB), hemorragia (H), profundidad de la bolsa (PS) y nivel de inserción clínica (NIC) en cada momento del tratamiento. Se tomaron muestras de la profundidad de las bolsas para identificar bacterias periodontales por biología molecular. Resultados: Se observó una mejoría de PB, H, PS y ganancia de NIC a lo largo de los 5 años. Con los injertos óseos la PS disminuyó 5 mm y de NIC se ganó 5 mm, con amelogeninas las diferencias fueron de 4,5 mm respectivamente. En colgajos de acceso, la PS disminuyó 3 mm y de NIC se ganó 2 mm. Se identificó T.denticola a los 36 meses, en todas las bolsas tratadas con colgajo de acceso y en el 50% de las bolsas con injertos óseos; y P. gingivalis a los 60 meses. Conclusiones: El tratamiento periodontal aplicado evitó la pérdida de los dientes afectados. El mejoramiento de los parámetros clínicos se asoció con una microbiota no agresiva.

Abstract Introduction: There are several techniques to treat and maintain teeth affected by stage III, grade C periodontitis, nonetheless, the scientific evidence available on how periodontal clinical parameters and microbiological composition may be modified during the conventional and surgical treatment is scarce. Objective: To evaluate the clinical and microbiological response of a patient with stage III grade C, generalized periodontitis, during 5 years, treated with non-surgical and surgical periodontal therapy using regenerative material and bone substitute. Methodology: The patient was treated with scaling and progressive root planning, combined with antibiotics and surgical therapy was performed in sites with infraosseous defects. At each time of treatment, subgingival bacterial plaque (PB), haemorrhage (H), probing depth (PD) and clinical attachment level (CAL) were recorded. To identify periodontal bacteria by molecular biology samples were taken with endodontic cones from the pocket depth. Results: A significant difference of PB, H, PD was observed. The PD decreased and CAL was gained throughout the treatment. PD decreased 5 mm with the application of bone substitute, and CAL gained 5 mm, with the use of amelogenins the difference of PD and CAL was 4.5 mm. In access flap the PD decreased 3 mm and the CAL improved 2 mm. T. denticola was identified at 36 months in all pockets treated with access flap and in 50% of the pockets with bone graft, and P. gingivalis at 60 months. Conclusions: The periodontal treatment applied prevented the loss of the affected teeth. Improvement of clinical parameters was associated with a non-aggressive microbiota.

The effect of ellagic acid on the repair process of periodontal defects related to experimental periodontitis in rats

Abstract Objective This study aims to evaluate the effect of ellagic acid (EA) by measuring the levels of alveolar bone resorption and inflammatory and oxidative stress markers in the periodontal tissues and serum on the periodontal repair process related to experimental periodontitis in rats. Methodology Forty Wistar rats were divided into four study groups as follows: Group 1=healthy control (n=10); Group 2=EA control (15 mg/kg)(n=10); Group 3=periodontitis (n=10); Group 4=periodontitis+EA (15 mg/kg) (n=10). The periodontitis model was established by ligating bilateral mandibular first molars for 14 days. Then, rats were given normal saline or EA for another 14 days by gavage administration. Serum and gingiva myeloperoxidase (MPO) activity, 8-hydroxydeoxyguanosine(8-OHdG), and glutathione (GSH) levels were analyzed by ELISA. İmmunohistochemical analysis was used to detect Interleukin (IL)-6, IL-10, and tumor necrosis factor-alpha (TNF-α) immunoreactivities in the periodontal tissues. Alveolar bone loss (ABL) and attachment loss (AL) was evaluated by histomorphometry analysis. Results ABL and AL were statistically higher in group 3 than in groups 1, 2 and 4 and in group 4 than in groups 1 and 2 (p<0.05). MPO activities in gingival tissue and serum were significantly increased in group 3 compared to groups 1 and 2 (p<0.05). Significantly higher serum GSH levels, lower gingiva, and serum 8-OHdG levels, and MPO activity were observed in group 4 compared to group 3 (p<0.05). Rats with periodontitis (group 3) expressed significantly higher immunoreactivities of IL-6 and TNF-α and lower IL-10 immunoreactivity compared to those other groups (p<0.05). IL-6 and TNF-α immunoreactivities significantly decreased and IL-10 immunoreactivity increased in group 4 after the use of EA compared to group 3 (p<0.001). Conclusions Our findings showed that EA provides significant improvements on gingival oxidative stress and inflammatory markers and alveolar bone resorption in the repair process associated with experimental periodontitis. Therefore, EA may have a therapeutic potential on periodontitis.

Evaluation of the effect of topical and systemic ozone application in periodontitis: an experimental study in rats

Abstract Objective: The goal of the present study was to determine the effect of systemic and topical ozone application on alveolar bone loss (ABL) by evaluating the effect of Hypoxia-inducible factor −1 alpha (HIF-1-α) and receptor activator of NF-kB ligand (RANKL)-positive cells on histopathological and immunohistochemical changes in a rat periodontitis model. Methodology: Thirty male Wistar rats were divided into three groups: 1) Group C (control group); 2) Group SO (systemic ozone group) and 3) Group TO (topical ozone group). Experimental periodontitis was induced with a 3/0 silk suture placed at the mandibular left first molars of rats, and the suture was removed 14 days later. Ozone gas was injected intraperitoneally (0.7 mg/kg) in SO group. Topical ozone application protocol was performed using an ozone generator at 80% concentration (4th grade) 90- degree probe for the duration of 30 s. Both ozone applications were carried out for two weeks at intervals of two days. Histomorphometric and immunohistochemical analysis were performed. Results: ABL was significantly lower in Group SO compared to Group C (p: 0.0052). HIF-1α- positive cells were significantly lower in Group TO than in Group C (p: 0.0043). RANKL-positive cells were significantly lower in Group SO and in Group TO compared to the control group (p: 0.0033, p: 0.0075, respectively). Conclusion: Both ozone applications decreased RANKL-positive cell counts, TO application decreased HIF-1-α positive cells counts, and SO application was found to be more effective in reducing ABL compared to control group.

Effects of vitamin C local application on ligature-induced periodontitis in diabetic rats

Abstract Objective: This study evaluated the effects of local vitamin C treatment on tissue advanced glycation end products (AGE), interleukin (IL)-6, 8-hydroxy-2-deoxyguanosine (8-OHdG), and matrix metalloproteinases (MMP)-8 in tissues; serum C-terminal telopeptide fragments (CTX); and alveolar bone loss (ABL) in rats. Methodology: 35 male Sprague Dawley rats were divided equally into five groups: 1) control (C), 2) experimental periodontitis (P), 3) experimental diabetes (D), 4) experimental diabetes and experimental periodontitis (D + P), and 5) experimental diabetes-experimental periodontitis-locally applied vitamin C (D + P + LvitC). Diabetes was induced in rats with alloxan monohydrate, after which periodontitis was induced by ligature placement in the right mandibular first molar teeth for 11 days. In the treatment group, vitamin C was administered locally three times with two-days interval after ligature removal. The animals were sacrificed, and the samples were analyzed histometrically and immunohistochemically. Results: CTX, 8-OHdG, and AGE values significantly decreased in the treatment group compared to the D + P group. IL-6 and MMP-8 values decreased in the treatment group compared to the D + P group, but this is not significant. ABL was significantly reduced by the local delivery of vitamin C. Conclusion: This study reveals that vitamin C treatment may be beneficial to reduce serum CTX and gingival MMP-8 levels, oxidative stress, inflammation, and AGE accumulation in periodontal tissue. Vitamin C may be an immunomodulator and antioxidant locally applied in the treatment of periodontitis to reduce the adverse effects of diabetes in periodontal tissues.

Parathyroid hormone increases alveolar bone homoeostasis during orthodontic tooth movement in rats with periodontitis via crosstalk between STAT3 and β-catenin / 国际口腔科学杂志·英文版

Periodontitis patients are at risk of alveolar bone loss during orthodontic treatment. The aim of this study was to investigate whether intermittent parathyroid hormone (1-34) treatment (iPTH) could reduce alveolar bone loss during orthodontic tooth movement (OTM) in individuals with periodontitis and the underlying mechanism. A rat model of OTM in the context of periodontitis was established and alveolar bone loss was observed. The control, iPTH and iPTH + stattic groups received injections of vehicle, PTH and vehicle, or PTH and the signal transducer and activator of transcription 3 (STAT3) inhibitor stattic, respectively. iPTH prevented alveolar bone loss by enhancing osteogenesis and suppressing bone resorption in the alveolar bone during OTM in rats with periodontitis. This effect of iPTH was along with STAT3 activation and reduced by a local injection of stattic. iPTH promoted osteoblastic differentiation and might further regulate the Wnt/β-catenin pathway in a STAT3-dependent manner. The findings of this study suggest that iPTH might reduce alveolar bone loss during OTM in rats with periodontitis through STAT3/β-catenin crosstalk.

Efeito do fotossensibilizador butyl azul de toluidina na terapia fotodinâmica antimicrobiana para o tratamento da periodontite experimental em ratos / Effects of butyl toluidine blue photosensitizer on antimicrobial photodynamic therapy for experimental periodontitis treatment in rats

O presente estudo avaliou pela primeira vez "in vivo" os efeitos de três concentrações do butyl azul de toluidina (BuTB) como agente fotossensibilizador na terapia fotodinâmica antimicrobiana (aPDT), como terapia coadjuvante a raspagem e alisamento radicular (RAR), para o tratamento de periodontite experimental (PE) em ratos. A PE foi induzida por meio da instalação de um fio de algodão ao redor do primeiro molar inferior esquerdo. Posteriormente os animais foram aleatoriamente distribuídos em 7 grupos com 15 animais cada, através de uma tabela gerada por computador, de acordo com os seguintes tratamentos: RAR (n=15) - RAR seguido de irrigação local de solução salina fisiológica; BuTB-0,1 (n=15) - RAR seguido de aplicação local de BuTB na concentração de 0,1 mg/mL; aPDT-0,1 (n=15) - RAR seguido da aplicação local de BuTB na concentração de 0,1 mg/mL e irradiação com laser de diodo (LD) de InGaAlP (660 nm, 40 mW, 60 s, 2,4 J); BuTB-0,5 (n=15) ­ RAR seguido de aplicação local de BuTB na concentração de 0,5 mg/mL; aPDT-0,5 (n=15) ­ RAR seguido da aplicação local de BuTB na concentração de 0,5 mg/mL e irradiação com LD; BuTB-2,0 (n=15) - RAR seguido de aplicação local de BuTB na concentração de 2 mg/mL; aPDT-2,0 (n=15) - RAR seguido da aplicação local de BuTB na concentração de 2 mg/mL e irradiação com LD. Decorridos 7, 15 e 30 dias pós-tratamento, 5 animais de cada grupo foram submetidos à eutanásia. A área de furca dos molares foi submetida às análises histológica, histométrica e dos padrões de imunomarcação para TGF-ß1, OCN e TRAP. Os dados foram submetidos à análise estatística (α = 5%). De acordo com a análise histométrica na região de furca, todos os grupos experimentais apresentaram menor perda óssea comparado ao grupo controle. Histologicamente, os espécimes do aPDT-0,5 apresentaram uma resposta inflamatória local mais branda e menos extensa, com melhor reestruturação tecidual em todos os períodos. Aos 30 dias observou-se resolução total da resposta inflamatória local, com presença de tecido conjuntivo denso. Alguns espécimes apresentavam trabéculas ósseas com contorno regular revestido com osteoblastos ativos, incluindo áreas de neoformação óssea. O tratamento com aPDT na concentração de 0,5 mg/mL resultou em padrões mais altos de imunomarcação de TGF-ß1 em todos os períodos e de OCN aos 30 dias. Diante dos resultados obtidos, todas as concentrações do novo fotossensibilizador BuTB trouxeram resultados adicionais ao tratamento da PE em relação a RAR. No entanto, a aPDT realizada com a concentração de 0,5 mg/mL resultou em benefícios adicionais na resposta inflamatória local e melhor reestruturação tecidual(AU)

The present study evaluated for the first time the effects of three concentrations of butyl toluidine blue (BuTB) as a photosensitizing agent on antimicrobial photodynamic therapy (aPDT), as adjuvant therapy to scaling and root planing (SRP), for the treatment of experimental periodontitis (EP) in rats. EP was induced by placing a cotton thread around the lower left first molar. Subsequently, the animals were randomly distributed into seven groups with 15 animals each, through a computer generated table, according to the following treatments: SRP (n = 15), SRP followed by local irrigation of physiological saline solution; BuTB-0.1 (n = 15), SRP followed by local application of 0.1 mg/mL BuTB; aPDT-0.1 (n = 15), SRP followed by local application of BuTB at 0.1 mg/mL concentration and irradiation with InGaAlP diode laser (DL) (660 nm, 40 mW, 60 s, 4 J); BuTB-0.5 (n = 15), SRP followed by local application of BuTB at 0.5 mg/mL concentration; aPDT-0.5 (n = 15), SRP followed by local application of BuTB at 0.5 mg/mL concentration and DL irradiation; BuTB-2.0 (n = 15), SRP followed by local application of BuTB at 2 mg/mL concentration; aPDT-2.0 (n = 15), SRP followed by local application of BuTB at 2 mg/mL concentration and DL irradiation. The animals (n=5) from each group were submitted to euthanasia at 7, 15 and 30 days post-treatment. The furcation area of the first lower molar was submitted to histological, histometric and immunohistochemical analyses to identify TGF-ß1, OCN and TRAP. The data were submitted to statistical analysis (α = 5%). According to the histometric analysis in the furcation region, all experimental groups presented lower bone loss compared to the control group. Histologically, the aPDT -0.5 specimens presented a milder and less extensive local inflammatory response, with better tissue remodeling in all periods. Total resolution of the local inflammatory response was observed at 30 days with presence of mature connective tissue. Some specimens presented bone trabeculae with a regular contour and active osteoblasts, including areas of bone neoformation. Treatment with aPDT-0.5 also resulted in higher immunolabelling patterns of TGFß1 at all periods and of OCN at 30 days. All concentrations of the new photosensitizer BuTB resulted in significant improvement for EP treatment in relation to SRP. However, aPDT combined with BuTB at 0.5 mg / mL showed the best benefits for inflammatory response and periodontal repair process(AU)

Effects of astragaloside IV on inflammation and immunity in rats with experimental periodontitis

Abstract: This study aimed to investigate the effects of astragaloside IV (AsIV) on inflammation and immunity in rats with experimental periodontitis. Periodontitis was established in 48 Wistar rats, which were then randomly divided into model and 10, 20 and 40 mg/kg AsIV groups, with 12 rats in each group. The latter 3 groups were treated with AsIV at doses of 10, 20 and 40 mg/kg, respectively. The control group (12 rats, without periodontitis) and model group were given the same amount of 5% sodium carboxymethyl cellulose. The treatment was performed once per day for 8 weeks. Before and after treatment, the tooth mobility scores of the rats were determined. After treatment, the salivary occult blood index (SOBI), plaque index (PLI), peripheral blood T lymphocyte subsets, and serum inflammatory factor and immunoglobulin levels were determined. The results showed that, after treatment, compared with that in model group, in 40 mg/kg AsIV group, the general state of rats was improved, while the tooth mobility score, SOBI and PLI were significantly decreased (p < 0.05); the peripheral blood CD4+ T cell percentage and CD4+/CD8+ ratio were significantly increased (p < 0.05), while the CD8+ T cell percentage was significantly decreased (p < 0.05); the serum tumor necrosis factor-α, interleukin-1β and interleukin-2 levels were significantly decreased (p < 0.05); the serum immunoglobulin A and immunoglobulin G levels were significantly decreased (p < 0.05). In conclusion, AsIV can alleviate inflammation and enhance immunity in rats with experimental periodontitis.

Effect of avocado/soybean unsaponifiables on periodontal repair in rats with arthritis and induced periodontitis

Abstract Objective: This study aimed to evaluate the effect of avocado/soybean unsaponifiables (ASU) on periodontal repair in rats with induced periodontitis and arthritis. Methodology: Forty-five rats were submitted to periodontitis induction by insertion of ligatures into the upper second molars, maintained for 15 days. These animals were randomly allocated to 3 groups according to the presence of induced arthritis (ART) and the application of the ASU: Control (CTR) group-healthy animals, where saline solution was administered; ART-animals with induced arthritis, where saline solution was administered; ART/ASU-animals with induced arthritis, where ASU (0.6 mg/ kg) was administered. The drugs were administered daily by gavage and the animals were euthanized after 7, 15 and 30 days of the ligature removal. Bone resorption, inflammatory infiltrate composition and marker proteins expression of the differentiation and formation of osteoclasts (RANKL and TRAP) were assessed. Results: The ART/ASU group presented higher bone volume than the ART group at 7 and 30 days after the ligature removal. Furthermore, the ART group presented higher quantity of inflammatory cells and expression of TRAP and RANKL than the other groups. Conclusion: ASU administration improves the repair of periodontal tissues in an experimental periodontitis model in rats with induced arthritis.

Gliclazide reduced oxidative stress, inflammation, and bone loss in an experimental periodontal disease model

Abstract Objective The aim of this study was to evaluate the effects of gliclazide on oxidative stress, inflammation, and bone loss in an experimental periodontal disease model. Material and Methods Male albino Wistar rats were divided into no ligature, ligature, and ligature with 1, 5, and 10 mg/kg gliclazide groups. Maxillae were fixed and scanned using micro-computed tomography to quantify linear and bone volume/tissue volume (BV/TV) and volumetric bone loss. Histopathological, immunohistochemical and immunofluorescence analyses were conducted to examine matrix metalloproteinase-2 (MMP-2), cyclooxygenase 2 (COX-2), cathepsin K, members of the receptor activator of the nuclear factor kappa-Β ligand (RANKL), receptor activator of nuclear factor kappa-Β (RANK), osteoprotegerin (OPG) pathway, macrophage migration inhibitory factor (MIF), superoxide dismutase-1 (SOD-1), glutathione peroxidase-1 (GPx-1), NFKB p 50 (Cytoplasm), NFKB p50 NLS (nuclear localization signal), PI3 kinase and AKT staining. Myeloperoxidase activity, malondialdehyde and glutathione levels, while interleukin-1 beta (IL-1β) and tumor necrosis factor-alpha (TNF-α) levels were evaluated by spectroscopic ultraviolet-visible analysis. A quantitative reverse transcription polymerase chain reaction was used to quantify the gene expression of the nuclear factor kappa B p50 subunit (NF-κB p50), phosphoinositide 3-kinase (PI3k), protein kinase B (AKT), and F4/80. Results Micro-computed tomography showed that the 1 mg/kg gliclazide treatment reduced linear bone loss compared to the ligature, 5 mg/kg gliclazide, and 10 mg/kg gliclazide treatments. All concentrations of gliclazide increased bone volume/tissue volume (BV/TV) compared to the ligature group. Treatment with 1 mg/kg gliclazide reduced myeloperoxidase activity, malondialdehyde, IL-1β, and TNF-α levels (p≤0.05), and resulted in weak staining for COX-2, cathepsin k, MMP-2, RANK, RANKL, SOD-1, GPx-1,MIF and PI3k. In addition, down-regulation of NF-κB p50, PI3k, AKT, and F4/80 were observed, and OPG staining was strong after the 1 mg/kg gliclazide treatment. Conclusions This treatment decreased neutrophil and macrophage migration, decreased the inflammatory response, and decreased bone loss in rats with ligature-induced periodontitis.

The effect of colchicine on alveolar bone loss in ligature-induced periodontitis

Abstract Colchicine is widely used in the treatment of several inflammatory diseases due to its anti-inflammatory effect, but effects on bone metabolism are unclear. The aim of this study was to evaluate the effects of systemically-administered colchicine on healthy periodontium and experimentally-induced periodontitis. In total, 42 male Wistar rats were included in this study. A non-ligated group constituting the negative control group (Control, C, n = 6) and a ligature-only group forming the positive control group (LO, n = 12) were created separately. Twelve rats were treated with 0.4 mg/kg colchicine and another 12 with 1 mg/kg colchicine. In the colchicine-administered groups, right mandibles constituted the ligated groups (1 mgC-L or 0.4 mgC-L) and left mandibles formed the corresponding non-ligated controls (1mgC or 0.4mgC). Silk ligatures were placed at the gingival margin of the lower first molars. The animals were euthanized at different time-points of healing (11 or 30 days). Alveolar bone loss was clinically measured and TRAP+ osteoclasts, osteoblastic activity, and MMP-1 expression were examined histologically. There was no increase in alveolar bone loss with either colchicine dose in healthy periodontium (p > 0.05) and the highest level of alveolar bone loss, TRAP+ osteoclast number, and MMP-1 expression were measured in the LO group (p < 0.05). The 0.4 mgC-L group showed less alveolar bone loss at 11 days (p < 0.05), but greater loss at 30 days. The 1 mgC-L group showed higher osteoblast number than the other ligated groups (p < 0.05) at both time-points. In summary, colchicine did not increase alveolar bone loss in healthy periodontium and also may tend to reduce periodontitis progression. However, further extensive study is necessary to understand the mechanism of colchicine action on alveolar bone loss in periodontitis.

Effects of 1, 25-dihydroxyvitamin D3 on experimental periodontitis and AhR/NF-κB/NLRP3 inflammasome pathway in a mouse model

Abstract Vitamin D has been known to have important regulatory functions in inflammation and immune response and shows inhibitory effects on experimental periodontitis in animal models. However, the potential mechanism has yet to be clarified. Recent studies have highlighted Aryl hydrocarbon receptor (AhR) and its downstream signaling as a crucial regulator of immune homeostasis and inflammatory regulation. Objective: This study aimed to clarify the effect of 1,25-dihydroxyvitamin D3 (VD3) on experimental periodontitis and AhR/nuclear factor-κB (NF-κB)/NLR pyrin domain-containing 3 (NLRP3) inflammasome pathway in the gingival epithelium in a murine model. Methodology: We induced periodontitis in male C57BL/6 wild-type mice by oral inoculation of Porphyromonas gingivalis (P. gingivalis), and subsequently gave intraperitoneal VD3 injection to the mice every other day for 8 weeks. Afterwards, we examined the alveolar bone using scanning electron microscopy (SEM) and detected the gingival epithelial protein using western blot analysis and immunohistochemical staining. Results: SEM images demonstrated that alveolar bone loss was reduced in the periodontitis mouse model after VD3 supplementation. Western blot analyses and immunohistochemical staining of the gingival epithelium showed that the expression of vitamin D receptor, AhR and its downstream cytochrome P450 1A1 were enhanced upon VD3 application. Additionally, VD3 decreased NF-κB p65 phosphorylation, and NLRP3, apoptosis-associated speck-like protein, caspase-1, interleukin-1β (IL-1β) and IL-6 protein expression. Conclusions: These results implicate the alleviation of periodontitis and the alteration of AhR/NF-κB/NLRP3 inflammasome pathway by VD3 in the mouse model. The attenuation of this periodontal disease may correlate with the regulation of AhR/NF-κB/NLRP3 inflammasome pathway by VD3.

Oxymatrine alleviates periodontitis in rats by inhibiting inflammatory factor secretion and regulating MMPs/TIMP protein expression

Abstract Purpose: To investigate the effect of oxymatrine on periodontitis in rats and related mechanism. Methods: Ninety SD rats were divided into control, model, 10, 20 and 40 mg/kg oxymatrine and tinidazole groups. The periodontitis model was established in later 5 groups. The 10, 20 and 40 mg/kg oxymatrine groups were intragastrically administrated with 10, 20 and 40 mg/kg oxymatrine, respectively. The tinidazole group was intragastrically administrated with 100 mg/kg tinidazole. The treatment duration was 4 weeks. The tooth mobility, gingival and plaque indexes, serum inflammatory factor levels and gingival tissue matrix metalloproteinases (MMPs) and tissue inhibitor of metalloproteinase (TIMP) protein levels were detected. Results: After treatment, compared with model group, in 40 mg/kg oxymatrine group the rat general conditions were obviously improved, the tooth mobility, gingival index and plaque index were significantly decreased (P<0.05), the serum tumor necrosis factor-α, interleukin-1β and prostaglandin E2 levels were significantly decreased (P<0.05), the MMP-2 and MMP-9 protein levels were significantly decreased (P<0.05), and the TIMP-2 protein level was significantly increased (P<0.05). Conclusions: Oxymatrine can alleviate the experimental periodontitis in rats. The mechanism may be related to its inhibiting inflammatory factor secretion and regulating MMPs/TIMP protein expression.