Effects of Pera Orange Juice and Moro Orange Juice in Healthy Rats: A Metabolomic Approach.

Cardiovascular disease is a leading cause of death worldwide. Heart failure is a cardiovascular disease with high prevalence, morbidity, and mortality. Several natural compounds have been studied for attenuating pathological cardiac remodeling. Orange juice has been associated with cardiovascular disease prevention by attenuating oxidative stress. However, most studies have evaluated isolated phytochemicals rather than whole orange juice and usually under pathological conditions. In this study, we evaluated plasma metabolomics in healthy rats receiving Pera or Moro orange juice to identify possible metabolic pathways and their effects on the heart. METHODS: Sixty male Wistar rats were allocated into 3 groups: control (C), Pera orange juice (PO), and Moro orange juice (MO). PO and MO groups received Pera orange juice or Moro orange juice, respectively, and C received water with maltodextrin (100 g/L). Echocardiogram and euthanasia were performed after 4 weeks. Plasma metabolomic analysis was performed by high-resolution mass spectrometry. Type I collagen was evaluated in picrosirius red-stained slides and matrix metalloproteinase (MMP)-2 activity by zymography. MMP-9, tissue inhibitor of metalloproteinase (TIMP)-2, TIMP-4, type I collagen, and TNF-α protein expression were evaluated by Western blotting. RESULTS: We differentially identified three metabolites in PO (N-docosahexaenoyl-phenylalanine, diglyceride, and phosphatidylethanolamine) and six in MO (N-formylmaleamic acid, N2-acetyl-L-ornithine, casegravol isovalerate, abscisic alcohol 11-glucoside, cyclic phosphatidic acid, and torvoside C), compared to controls, which are recognized for their possible roles in cardiac remodeling, such as extracellular matrix regulation, inflammation, oxidative stress, and membrane integrity. Cardiac function, collagen level, MMP-2 activity, and MMP-9, TIMP-2, TIMP-4, type I collagen, and TNF-α protein expression did not differ between groups. CONCLUSION: Ingestion of Pera and Moro orange juice induces changes in plasma metabolites related to the regulation of extracellular matrix, inflammation, oxidative stress, and membrane integrity in healthy rats. Moro orange juice induces a larger number of differentially expressed metabolites than Pera orange juice. Alterations in plasma metabolomics induced by both orange juice are not associated with modifications in cardiac extracellular matrix components. Our results allow us to postulate that orange juice may have beneficial effects on pathological cardiac remodeling.

Effects of Laser Irradiation on Pulp Cells Exposed to Bleaching Agents.

The aim of this study was to evaluate the effect of low-level laser therapy (LLLT) on odontoblast-like cells exposed to a bleaching agent. Mouse dental papilla cell-23 cells were seeded in wells of 24-well plates. Eight groups were established according to the exposure to the bleaching agent and LLLT (0, 4, 10 and 15 J cm(-2) ). Enamel-dentin disks were adapted to artificial pulp chambers, which were individually placed in wells containing Dulbecco's modified Eagle's medium (DMEM). A bleaching agent (35% hydrogen peroxide [BA35%HP]) was applied on enamel (15 min) to obtain the extracts (DMEM + BA35%HP components diffused through enamel/dentin disks). The extracts were applied (1 h) to the cells, and then subjected to LLLT. Cell viability (Methyl tetrazolium assay), alkaline phosphatase (ALP) activity, as well as gene expression of ALP, fibronectin (FN) and type I collagen, were evaluated. The bleaching procedures reduced the cell viability, ALP activity and gene expression of dentin proteins. Laser irradiation did not modulate the cell response; except for FN, as LLLT decreased the gene expression of this protein by the cells exposed to the BA35%HP. It can be concluded that BA35%HP decreased the activities of odontoblasts that were not recovered by the irradiation of the damaged cells with low-level laser parameters tested.

Efeito de um gel de peróxido de carbamida a 10% sobre a resistência de união de restaurações adesivas à dentina / Effect of a 10% carbamide peroxide bleaching gel on bond strength of adhesive restorations to dentin substrate

Objetivo: Este estudo teve como objetivo principal, analisar a interferência do clareamento dentário com peróxido de carbamida (PC) a 10% sobre a resistência de união à dentina de restaurações de resina composta. Material e Método: Vinte cavidades foram preparadas na face vestibular de dentes bovinos. Após condicionamento ácido e aplicação de agente adesivo nas paredes de dentina e esmalte, as cavidades foram restauradas com resina composta. Os espécimes foram divididos em grupos de acordo com tratamento na superfície de esmalte/restauração: G1 ? controle (sem tratamento) e G2 (aplicação do gel de PC por 8h/dia, durante 14 dias). Após esse período, foram obtidos os corpos-de-prova em forma de palito com secção transversal de aproximadamente 0,81 mm2, os quais foram submetidos ao ensaio de microtração. As fraturas foram analisadas em lupa estereoscópica e classificadas em: coesiva da resina ou dentina, adesiva ou mista. Resultados: A análise estatística (ANOVA/ ?2) revelou que o fator tratamento interferiu na resistência adesiva, sendo que a resistência de união foi significantemente superior para os espécimes do grupo G2 (p<0,05). Fraturas adesivas predominaram em todos os grupos com valores que variaram de 48,3% a 75%. Fraturas mistas foram às segundas mais observadas em G1 e falhas coesivas da resina para G2. Conclusões: Conclui-se que o clareamento caseiro utilizando gel com 10% de PC aumentou a resistência de união de restaurações adesivas à dentina.

Objective: The present study aimed to analyze the effects of tooth bleaching with 10% carbamide peroxide (CP) gel on the bond strength of resin composite restorations to dentin. Material and Methods: Twenty cavities were prepared on the buccal surface of bovine teeth. After acid etching and application of bonding agent on dentin and enamel, the cavities were restored with composite resin. The specimens were divided into groups according to treatment on the surface of enamel / restoration: G1 - control (no treatment) and G2 (10% PC gel application for 8h/day during 14 days). After this period, the teeth were cut to produce beams with 0.81 mm2 cross-sectional area, which were subjected to microtensile test. The fractures were examined with a stereomicroscope and classified as cohesive in resin or dentin, adhesive, or mixed. Results: The statistical analysis (ANOVA / ?2) revealed that the factor treatment interfered with the bond strength, which was significantly higher for specimens of G2 (p <0.05). Adhesive fractures occurred in most of specimens of both groups with values ranging from 48.3% to 75%. Mixed fractures were the second more frequent in G1 and cohesive resin failure in G2. Conclusion: It was concluded that tooth bleaching with 10% of PC increased the bond strength of adhesive restorations to dentin.

Relação entre materiais dentários e o complexo dentino-pulpar / Relationship between dental materials and the dentin-pulp complex

Mesmo diante da valorização dos princípios estéticos e mecânicos dos materiais restauradores, os fatores biológicos são de extrema importância para a manutenção da vitalidade do complexo dentino-pulpar e devem ser levados em consideração para se obter o sucesso dos procedimentos clínicos. A dentina e tecido pulpar estão susceptíveis a diversos tipos de agressores que vão desde toxinas derivadas de microrganismos até aqueles originados por preparos cavitários erroneamente executados e materiais dentários tóxicos. Inicialmente, a polpa reage desencadeando um processo inflamatório que envolve fluido dentinário, odontoblastos, células do sistema imune e suas citocinas inflamatórias, além de neuropeptídeos e quimiocinas. Posteriormente poderá ocorrer resolução do quadro inflamatório, esclerose dentinária associada ou não a formação de dentina reacional ou reparadora. Caso a agressão seja de alta intensidade ou persista por um período longo, poderá ocorrer morte dos odontoblastos com consequente envelhecimento pulpar ou até mesmo necrose desse tecido conjuntivo especializado. Sendo assim, é de extrema importância o conhecimento dos aspectos fisiológicos e patológicos da polpa dentária assim como das conseqüências das intervenções realizadas diariamente na clínica. Dessa forma, o profissional poderá executar uma técnica operatória minimamente agressiva e selecionar materiais dentários adequados para serem utilizados dentro de cada situação clínica específica, visando à manutenção da integridade do complexo dentino-pulpar.

Despite the strong valorization of the esthetics and its relationship with restorative materials, the biological principles of any clinical procedure are extremely important to maintain the vitality of the dentin-pulp complex. Dentin and pulp tissue are susceptible to different kinds of irritants such as toxins from microorganisms, traumatic procedures of cavity preparation, as well as toxic components released by restorative materials applied in non recommended clinical situations. Initially, the pulp responds to irritation by starting an inflammatory reaction which involves outward movement of dentinal fluid and intratubular deposition of immunoglobulins, upregulation of odontoblast activities, presence of immune cells and their cytokines as well as local expression of neuropeptides and chemokines. After these initial events, the inflammation process can be resolved associated or not to sclerotic dentin formation and reactionary dentin deposition. If high intensity offensive stimuli are applied to the dentin-pulp complex, death of odontoblasts takes place and consequently pulp ageing or even partial necrosis of this tissue may occurs. Thereby, clinicians need to be aware about the physiological and pathological features of the dentin-pulp complex as well as the possible biological consequences of different clinical procedures. In this way, the dentists should be able to carry out minimally aggressive operative techniques and to select the more appropriate restorative materials for each specific clinical situation in order to obtain excellent clinical results associated to the maintenance of pulp vitality.

Efeito citotóxico de agentes clareadores a base de peróxido de hidrogênio a 20% e 38% sobre células odontoblastóides / Cytotoxic effect of a 20% and a 38% hydrogen peroxide bleaching agents on odontoblast-like cells

O objetivo deste estudo foi avaliar a citotoxicidade de diferentes técnicas de clareamento dentário, utilizando agentes clareadores com 20% e 38% de peróxido de hidrogênio (H2O2) sobre células odontoblastóides MDPC-23. Sessenta discos de esmalte/dentina foram adaptados em câmaras pulpares artificiais e divididos em seis grupos de acordo com o tratamento realizado sobre a superfície do esmalte: G1- 20% H2O2 (1 aplicação); G2- 20% H2O2 (2 aplicações); G3- 38% H2O2 (1 aplicação); G4- 38% H2O2 (2 aplicações); G5- 38% H2O2 (3 aplicações) e G6- controle. Em cada aplicação, os agentes clareadores com 20% ou 38% de H2O2 permaneceram sobre o esmalte por 45 ou 10 minutos, respectivamente. Após a última aplicação do gel, o meio de cultura em contato com a dentina foi obtido (extrato) e aplicado sobre as células previamente cultivadas (30.000 células/cm2). Foram realizadas avaliações do metabolismo (Teste de MTT) e da morfologia celular (MEV). A redução do metabolismo celular foi de 96,29%; 96,11%; 96,42%; 95,62% e 97,18% para G1, G2, G3, G4 e G5, respectivamente. Houve diferença estatisticamente significante apenas quando se comparou os grupos tratados com o grupo controle (G6) (Mann Whitney, p<0,05). Nestes grupos tratados, as poucas célulasque sobreviveram aos extratos apresentavam notáveis alterações morfológicas. Concluiu-se que ambas as técnicas de clareamento avaliadas resultaram em intenso efeito citotóxico trans-amelodentinário para ascélulas MDPC-23.

The aim of this in vitro study was to evaluate the trans-enamel and transdentinal cytotoxic effects of two in-office tooth bleaching techniques that employ bleaching gels containing 20% and 38% of H2O2 on cultured odontoblast-like cell line (MDPC-23). Sixty enamel/dentin discs were obtained from bovine central incisors and placed individually in artificial pulp chambers. Six groups were formed according to the following enamel treatments: G1- 20% H2O2 (1 application); G2- 20% H2O2 (2 applications); G3- 38% H2O2 (1 application); G4- 38% H2O2 (2 applications); G5- 38% H2O2 (3 applications); and G6- control (no treatment). In G1 and G2, the bleaching gel was left in contact with the enamel surface for 45 min in each application. However, in G3, G4, and G5 the bleaching gel was applied for only 10 min per application. After the last application, the extracts were collected and applied on previously cultured cells (30.000 cells/cm2) for 24 h. Cell metabolism was evaluated by the MTT assay and cell morphology was analysed by scanning electron microscopy. Cell metabolism decreased by 96.29%; 96.11%; 96.42%; 95.62%; and 97.18% in G1, G2, G3, G4, and G5, respectively. All treated groups differed significantly from non-treated control group (G6) (p < 0.05). However, the difference in cell metabolism among treated groups was not significant statistically. In addition, significant morphological cell alterations were observed in all treated groups. Under the tested experimental conditions, the extracts collected after both tooth bleaching techniques evaluated in this study caused severe toxic effects on cultured odontoblast-like cell MDPC-23.