RESUMEN
Fluoride (F) has been employed worldwide to control dental caries. More recently, it has been suggested that the consumption of low doses of F in the drinking water may reduce blood glucose levels, introducing a new perspective for the use of F for the management of blood glucose. However, the exact mechanism by which F affects blood glucose levels remains largely unexplored. Given that the small gut plays a pivotal role in glucose homeostasis, the aim of this study was to investigate the proteomic changes induced by low doses of F in the ileum of female nonobese-diabetic (NOD) mice. Forty-two female NOD mice were divided into two groups based on the F concentration in their drinking water for 14 weeks: 0 (control) or 10 mgF/L. At the end of the experimental period, the ileum was collected for proteomic and Western blot analyses. Proteomic analysis indicated an increase in isoforms of actin, gastrotropin, several H2B histones, and enzymes involved in antioxidant processes, as well as a decrease in enzymes essential for energy metabolism. In summary, our data indicates an adaptive response of organism to preserve protein synthesis in the ileum, despite significant alterations in energy metabolism typically induced by F, therefore highlighting the safety of controlled fluoridation in water supplies.
Asunto(s)
Caries Dental , Agua Potable , Ratones , Animales , Femenino , Fluoruros/farmacología , Fluoruros/análisis , Ratones Endogámicos NOD , Glucemia/análisis , Proteómica , Agua Potable/análisis , Íleon/química , Íleon/metabolismoRESUMEN
INTRODUCTION: The identification of acid-resistant proteins, including hemoglobin (Hb), within the acquired enamel pellicle (AEP) led to the proposition of the "acquired pellicle engineering" concept, which involves the modification of the AEP by incorporating specific proteins, presenting a novel strategy to prevent dental demineralization. OBJECTIVE: Combining in vivo and in vitro proof-of-concept protocols, we sought to reveal the impact of AEP engineering with Hb protein on the biofilm microbiome and enamel demineralization. METHODS: In the in vivo studies, 10 volunteers, in 2 independent experiments, rinsed (10 mL,1 min) with deionized water-negative control or 1.0 mg/mL Hb. The AEP and biofilm formed along 2 or 3 h, respectively, were collected. AEP was analyzed by quantitative shotgun-label-free proteomics and biofilm by 16S-rRNA next-generation sequencing (NGS). In in vitro study, a microcosm biofilm protocol was employed. Seventy-two bovine enamel specimens were treated with (1) phosphate-buffered solution (PBS), (2) 0.12% chlorhexidine, (3) 500 ppm NaF, (4) 1.0 mg/mL Hb, (5) 2.0 mg/mL Hb, and (6) 4.0 mg/mL Hb. The biofilm was cultivated for 5 days. Resazurin, colony forming units (CFU), and transversal microradiography were performed. RESULTS: Proteomics and NGS analysis revealed that Hb increased proteins with antioxidant, antimicrobial, acid-resistance, hydroxyapatite-affinity, calcium-binding properties and showed a reduction in oral pathogenic bacteria. In vitro experiments demonstrated that the lowest Hb concentration was the most effective in reducing bacterial activity, CFU, and enamel demineralization compared to PBS. CONCLUSION: These findings suggest that Hb could be incorporated into anticaries dental products to modify the oral microbiome and control caries, highlighting its potential for AEP and biofilm microbiome engineering.
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Biopelículas , Película Dental , Hemoglobinas , Antisépticos Bucales , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Hemoglobinas/análisis , Película Dental/microbiología , Humanos , Animales , Bovinos , Antisépticos Bucales/farmacología , Desmineralización Dental/prevención & control , Desmineralización Dental/microbiología , Adulto , Esmalte Dental/microbiología , Esmalte Dental/efectos de los fármacos , Masculino , ARN Ribosómico 16S , Femenino , Adulto Joven , Clorhexidina/farmacologíaRESUMEN
Results obtained from rat studies indicate that, even at low concentrations, mercurial species cause harmful effects on the kidneys, by inducing the nephrotic oxidative stress response. In the present work, Hg-associated proteins were identified as possible mercury-exposure biomarkers in rat kidneys exposed to low mercury chloride concentrations for 30 days (Hg-30) and 60 days (Hg-60), using metalloproteomic strategies. The renal proteomic profile was fractioned by two-dimensional electrophoresis and the mercury determinations in kidney samples, protein pellets and protein spots were performed using graphite furnace atomic absorption spectrometry. The characterization of Hg-associated protein spots and the analysis of differentially expressed proteins were performed by liquid chromatography, coupled with tandem mass spectrometry. Eleven Hg-associated protein spots with a concentration range of 79 ± 1 to 750 ± 9 mg kg-1 in the Hg-60 group were identified. The characterization and expression analyses allowed the identification of 53 proteins that were expressed only in the Hg-60 group, 13 "upregulated" proteins (p > 0.95) and 47 "downregulated" proteins (p < 0.05). Actin isoforms and hemoglobin subunits were identified in protein spots of the Hg-60 group, with mercury concentrations in the range of 138 to 750 mg kg-1, which qualifies these proteins as potential mercury-exposure biomarkers.
Asunto(s)
Desequilibrio Ácido-Base , Mercurio , Animales , Ratas , Proteínas Portadoras , Cloruros , Proteómica , Cloruro de Mercurio/toxicidad , Mercurio/toxicidad , BiomarcadoresRESUMEN
The current treatment of leishmaniasis is based on a few drugs that present several drawbacks, such as high toxicity, difficult administration route, and low efficacy. These disadvantages raise the necessity to develop novel antileishmanial compounds allied with a comprehensive understanding of their mechanisms of action. Here, we elucidate the probable mechanism of action of the antileishmanial binuclear cyclopalladated complex [Pd(dmba)(µ-N3)]2 (CP2) in Leishmania amazonensis. CP2 causes oxidative stress in the parasite, resulting in disruption of mitochondrial Ca2+ homeostasis, cell cycle arrest at the S-phase, increasing the reactive oxygen species (ROS) production and overexpression of stress-related and cell detoxification proteins, and collapsing the Leishmania mitochondrial membrane potential, and promotes apoptotic-like features in promastigotes, leading to necrosis, or directs programmed cell death (PCD)-committed cells toward necrotic-like destruction. Moreover, CP2 reduces the parasite load in both liver and spleen in Leishmania infantum-infected hamsters when treated for 15 days with 1.5 mg/kg body weight/day CP2, expanding its potential application in addition to the already known effectiveness on cutaneous leishmaniasis for the treatment of visceral leishmaniasis, showing the broad spectrum of action of this cyclopalladated complex. The data presented here bring new insights into the CP2 molecular mechanisms of action, assisting the promotion of its rational modification to improve both safety and efficacy.
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Antiprotozoarios , Leishmania infantum , Leishmaniasis Cutánea , Animales , Antiprotozoarios/uso terapéutico , Calcio/metabolismo , Muerte Celular , Leishmaniasis Cutánea/tratamiento farmacológico , Macrófagos , Ratones , Ratones Endogámicos BALB C , MitocondriasRESUMEN
Fluoride (F) at micromolar (µM) concentrations induces apoptosis in several cell lines. Moreover, proteomic studies have shown major changes in the profile of proteins involved in signal transduction. These effects may negatively affect ion transport in the kidneys. The activity of epithelial sodium channels (ENaCs) is a limiting factor for sodium and water resorption in the kidneys, which is essential for the maintenance of the electrolyte balance and homeostasis of the body. Here we investigated the effects of F, at different concentrations (10, 40, 100, 200, and 400 µM), on the viability of renal epithelial cells (M-1), and ENaC expression. We showed that sodium fluoride (NaF) reduces cell viability in a concentration-dependent manner (p < 0.05) up to a 96-h time-point when compared to control. Sodium fluoride at moderate concentrations (100 and 200 µM), upregulated the ENaC subunit genes Scnn1a and Scnn1g, but not Scnn1b. Sodium fluoride downregulated all three ENaC subunit genes at a higher concentration of 400 µM (p < 0.05). Immunofluorescence analysis showed that Scnn1a and Scnn1g expression was decreased within 24 h of NaF treatment. After 48 h, NaF (400 µM) increased the expression of Scnn1a but not Scnn1g. However, NaF decreased the expression of Scnn1g at all studied concentrations. We conclude that F, at µM concentrations, modulates the expression of ENaC subunit genes, which is likely to significantly affect molecular signaling in kidney epithelial cells.
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Fluoruros , Proteómica , Supervivencia Celular , Células Epiteliales , Fluoruros/toxicidad , RiñónRESUMEN
This study compared the protein profile of the acquired enamel pellicle (AEP) formed under three conditions: in vitro, in situ, and in vivo. Nine volunteers participated in all procedures. In the in vitro condition, the volunteers donated saliva, in which specimens were incubated to form the AEP. In the in situ condition, the volunteers used an oral device containing specimens where the AEP was formed. In the in vivo condition, the AEP was collected from the volunteers own teeth. All AEPs were formed for 120 min, collected and processed by mass spectrometry. Overall, a total of 321 proteins were identified, among which 37 proteins are commonly considered typical in the AEP. For each of the in vitro, in situ, and in vivo conditions, respectively, 66, 174, and 170 proteins were identified. For the in vitro condition, 17 pellicle-typical proteins were not identified. Furthermore, several proteins with important functions within the AEP presented differences in expression in the three conditions. The qualitative profile of the proteins, especially the typical ones, is different in the in vitro condition. In addition, there are important quantitative differences that may interfere when attempting to extrapolate in vitro results to an in situ and in vivo condition.
Asunto(s)
Proteómica , Saliva , Película Dental , Humanos , ProteínasRESUMEN
Diabetes mellitus is a disease that affects glucose homeostasis. The World Health Organization informs that there are over 347 million people in the world with diabetes. The diagnosis and characterization of glucose homeostasis in different metabolic conditions are subjects of great importance with high clinical impact. There are many mathematical models that describe the glucoregulatory system in detail. However, the use of these models is limited because they have a large number of mathematical equations and parameters and they require complex methodologies to estimate of them. This forced to work with average values that decrease the validity of results and the applicability of the models. In this study two mathematical models for rats with diabetes mellitus were developed. The difference between these models and others lies in the possibility of obtaining all parameters for each animal from simple measurements (glucose and insulin plasma levels). Moreover, the models allow to measure in vivo the different physiological processes involved in glucose homeostasis in animals: insulin secretion and its plasma clearance, absorption of insulin from a subcutaneous injection, the liver handling of glucose, intestine absorption of glucose, glucose uptake rate of insulin-independent tissues, glucose uptake rate of insulin-dependent tissues, and renal glucose excretion.
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Diabetes Mellitus Tipo 1/metabolismo , Glucosa/metabolismo , Homeostasis , Insulina/metabolismo , Hígado/metabolismo , Modelos Teóricos , Animales , Transporte Biológico , Glucemia/metabolismo , Simulación por Computador , Insulina/sangre , RatasRESUMEN
Fluoride exposure is widespread, with drinking water commonly containing natural and artificially added sources of the ion. Ingested fluoride undergoes absorption across the gastric and intestinal epithelia. Previous studies have reported adverse gastrointestinal effects with high levels of fluoride exposure. Here, we examined the effects of fluoride on the transepithelial ion transport and resistance of three intestinal epithelia. We used the Caco-2 cell line as a model of human intestinal epithelium, and rat and mouse colonic epithelia for purposes of comparison. Fluoride caused a concentration-dependent decline in forskolin-induced Cl- secretion and transepithelial resistance of Caco-2 cell monolayers, with an IC50 for fluoride of about 3 mM for both parameters. In the presence of 5 mM fluoride, transepithelial resistance fell exponentially with time, with a t1/2 of about 7 hours. Subsequent imaging by immunofluorescence and scanning electron microscopy showed structural abnormalities in Caco-2 cell monolayers exposed to fluoride. The Young's modulus of the epithelium was not affected by fluoride, although proteomic analysis revealed changes in expression of a number of proteins, particularly those involved in cell-cell adhesion. In line with its effects on Caco-2 cell monolayers, fluoride, at 5 mM, also had profound effects on Cl- secretion and transepithelial resistance of both rat and mouse colonic epithelia. Our results show that treatment with fluoride has major effects on the structure, function, and proteome of intestinal epithelia, but only at concentrations considerably higher than those likely to be encountered in vivo, when much lower fluoride doses are normally ingested on a chronic basis.
Asunto(s)
Fluoruros/farmacología , Mucosa Intestinal/efectos de los fármacos , Proteoma/efectos de los fármacos , Animales , Células CACO-2 , Adhesión Celular/efectos de los fármacos , Cloruros/metabolismo , Módulo de Elasticidad/efectos de los fármacos , Humanos , Mucosa Intestinal/fisiología , Ratones , Microscopía de Fuerza Atómica , Microscopía Electrónica de Rastreo , Microscopía Fluorescente , Técnicas de Placa-Clamp , Proteoma/metabolismo , RatasRESUMEN
High concentrations of fluoride in the body may cause toxic effects. Here, we investigated the effects of fluoride on the structure, function, and proteome of a cortical collecting duct epithelium in vitro. Kidney tubule cells (M-1) were chosen because the concentration of fluoride in the kidney is 4-5-fold higher than that in plasma. Mouse M-1 cell monolayers were incubated in fluoride-containing media, and the amiloride-sensitive short-circuit current and transepithelial resistance were measured. The Young's modulus of the epithelium was determined using atomic force microscopy, and the effect of fluoride on epithelial structure was assessed using scanning and transmission electron microscopy, and immunofluorescence. Differences in the expression of membrane proteins were evaluated using proteomics and bioinformatics. Fluoride exposure reduced both transepithelial Na+ transport and resistance. The IC50 for fluoride was â¼300 µM for both effects, and the half-times for the decays of ion transport and resistance were 8.4 h and 3.6 days, respectively. Fluoride treatment did not affect the sensitivity of Na+ transport to amiloride. The Young's modulus of the epithelium was also unaffected by fluoride; however, the functional effects of fluoride were accompanied by marked structural effects. Proteomic analysis revealed changes in expression of a number of proteins, and particularly mitochondrial proteins. Treatment with fluoride had profound effects on the structure, function and proteome of a model cortical collecting duct epithelium. Significantly, however, these effects were produced only at concentrations considerably higher than those likely to be encountered in vivo. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1455-1467, 2017.
Asunto(s)
Cariostáticos/toxicidad , Células Epiteliales/metabolismo , Proteoma/metabolismo , Fluoruro de Sodio/toxicidad , Animales , Células Cultivadas , Células Epiteliales/efectos de los fármacos , Transporte Iónico/efectos de los fármacos , Túbulos Renales/citología , Potenciales de la Membrana , Ratones , Mapas de Interacción de Proteínas , ProteómicaRESUMEN
OBJECTIVES: Calcium glycerophosphate (CaGP) was added to fluoride varnishes to analyze their preventive effect on initial enamel erosion and fluoride uptake: potassium hydroxide (KOH)-soluble and KOH-insoluble fluoride bound to enamel. MATERIALS AND METHODS: This study was carried out in two parts. Part 1: 108 enamel samples were randomly distributed into six varnish groups: base varnish (no active ingredients); Duraphat® (2.26%NaF); Duofluorid® (5.63%NaF/CaF2); experimental varnish 1 (1%CaGP/5.63 NaF/CaF2); experimental varnish 2 (5%CaGP/5.63%NaF/CaF2); and no varnish. Cyclic demineralization (90 s; citric acid, pH = 3.6) and remineralization (4 h) was made once a day, for 3 days. Change in surface microhardness (SMH) was measured. Part 2: 60 enamel samples were cut in half and received no varnish (control) or a layer of varnish: Duraphat®, Duofluorid®, experimental varnishes 1 and 2. Then, KOH-soluble and KOH-insoluble fluoride were analyzed using an electrode. RESULTS: After cyclic demineralization, SMH decreased in all samples, but Duraphat® caused less hardness loss. No difference was observed between varnishes containing CaGP and the other varnishes. Similar amounts of KOH-soluble and insoluble fluoride was found in experimental varnish 1 and Duofluorid®, while lower values were found for experimental varnish 2 and Duraphat®. CONCLUSION: The addition of CaGP to fluoride varnishes did not increase fluoride bound to enamel and did not enhance their protection against initial enamel erosion. CLINICAL RELEVANCE: We observe that the fluoride varnishes containing CaGP do not promote greater amounts of fluoride bound to enamel and that fluoride bound to enamel may not be closely related to erosion prevention.
Asunto(s)
Compuestos de Calcio/farmacología , Fluoruros Tópicos/farmacología , Glicerofosfatos/farmacología , Erosión de los Dientes/prevención & control , Compuestos de Calcio/química , Fluoruros Tópicos/química , Glicerofosfatos/química , Dureza , Humanos , Concentración de Iones de Hidrógeno , Técnicas In Vitro , Diente Molar , Distribución Aleatoria , Fluoruro de Sodio , Propiedades de SuperficieRESUMEN
This study used metalloproteomic techniques to characterize mercury (Hg)-bound proteins in the muscle and liver tissue of Tucunaré (Cichla spp.) collected at the Jirau Hydroelectric Power Plant in Madeira River Basin, Brazil. The proteome of the muscle and liver tissue was obtained after two steps of fractional precipitation and separating the proteins by 2-D polyacrylamide gel electrophoresis. Hg was identified and quantified in the protein spots by graphite furnace atomic absorption spectrometry after acid mineralization in an ultrasound bath. Hg with a molecular weight <20 kDa and a concentration between 13.30 and 33.40 mg g(-1) was found in the protein spots. These protein spots were characterized by electrospray ionization tandem mass spectrometry after trypsin digestion. From a total of 12 analyzed spots, seven proteins showing Hg biomarker characteristics were identified: parvalbumin and its isoforms, ubiquitin-40S ribosomal protein S27a, zinc (Zn) finger and BTB domain-containing protein 24, and dual-specificity protein phosphatase 22-B.
Asunto(s)
Cíclidos/metabolismo , Monitoreo del Ambiente , Mercurio/metabolismo , Contaminantes Químicos del Agua/metabolismo , Animales , Brasil , Electroforesis en Gel Bidimensional , Cadena Alimentaria , Hígado/metabolismo , Músculos , Centrales Eléctricas , Proteoma/metabolismo , Ríos/química , Espectrofotometría AtómicaRESUMEN
OBJECTIVES: This in situ/ex vivo study analysed the anti-erosive/abrasive effect of TiF4 and NaF varnish and solution on enamel wear. MATERIALS AND METHODS: Twelve subjects took part in this study which was performed in three periods (phases) with the duration of 5 days each. Each two human enamel specimens per subject were pretreated with experimental NaF varnish or solution (phase A), experimental-TiF4 varnish or solution (phase B) and placebo varnish or untreated control (phase C). The specimens were worn in palatal appliances; one enamel specimen, from each treatment, was subjected to erosion (ERO; cola soft drink, 4 × 90 s/day), and the other specimen was subjected to erosion plus abrasion (ERO + ABR; tooth brushing, 2 × 10 s/day). The tooth wear was quantified by a contact profilometer (micrometre) and analysed using two-way repeated measures ANOVA and Bonferroni's test (n = 12 subjects, p < 0.05). RESULTS: All fluoride varnishes and solutions reduced the enamel wear (around 25 %) significantly compared to the control and placebo varnish. There were no significant differences among the fluoride formulations and between the conditions ERO and ERO + ABR. CONCLUSIONS: Therefore, it can be concluded that TiF4 has the same protective potential as NaF formulations to reduce human enamel wear under this experimental in situ model. CLINICAL SIGNIFICANCE: In vitro studies have indicated a better anti-erosive/abrasive effect of TiF4 compared to NaF varnish. The present in situ study does not support the previous findings. Therefore, any of the tested professional fluoride varnishes in principle could be able to partially reduce enamel wear.
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Esmalte Dental/química , Fluoruros/química , Fluoruro de Sodio/química , Titanio/química , Fluoruros Tópicos , Humanos , SolucionesRESUMEN
OBJECTIVES: To perform a differential analysis of the dentin soluble proteomic and assess the effects of tissue health state and protocol for protein extraction. We hypothesized the dentin soluble proteomic varies according to the tissue physiopathological state (intact vs. caries-affected) and protocol used to extract its proteins. METHODS: Dentin from freshly extracted non-carious and carious teeth were randomly assigned for protein extraction using either guanidine-HCl/ethylenediaminetetraacetic acid (EDTA) or acetic acid. Protein extracts from intact and caries-affected dentin were processed and digested with trypsin for shotgun label-free proteomic analysis (nLC-ESI-MS/MS). Peptides identification was performed on a nanoACQUITY UPLC-Xevo Q-Tof MS system. Peptides identified with scores of confidence greater than 95% were included in the quantitative statistical analysis embedded in the PLGS software. Differences between experimental conditions were calculated using Student test-t with significance pre-set at α=0.05. RESULTS: A total of 158 human proteins were identified. Approximately one-sixth of proteins (24/158) were present in at least two different extracts. Conversely, the greatest number of proteins (134/158) was identified uniquely in only one of the extracts. Overall, a larger number of soluble proteins was retrieved from caries-affected than intact dentin (86/158). Likewise, a greater number of proteins was extracted by the guanidine-HCl/EDTA (106/158) in comparison to acetic acid protocol. Several proteins detected in dentin extracts, mainly those from caries-affected teeth, are biological and/or metabolically involved with tissue turnover/remodeling. CONCLUSION: The identity/abundance of soluble proteins retrieved from and remained in dentin noticeably depend on this tissue physiopathological state and protocol used to remove its minerals. CLINICAL SIGNIFICANCE: The present findings brought new insight into the proteomic phenotype of human dentin and may provide targets for the development of novel caries disease-prevention therapies.
Asunto(s)
Caries Dental , Dentina , Humanos , Caries Dental/metabolismo , Ácido Edético/farmacología , Guanidinas/metabolismo , Guanidinas/farmacología , Proteínas/metabolismo , Proteínas/farmacología , Proteómica , Espectrometría de Masas en TándemRESUMEN
Leukotrienes (LTs) are derived from arachidonic acid metabolism by the 5-lipoxygenase (5-LO) enzyme. The production of LTs is stimulated in the pathogenesis of rheumatoid arthritis (RA), osteoarthritis, and periodontitis, with a relevant contribution to bone resorption. However, its role in bone turnover, particularly the suppression of bone formation by modulating the function of osteoclasts and osteoblasts, remains unclear. We investigated the effects of LTs on bone metabolism and their impact on osteogenic differentiation and osteoclastogenesis using a 5-LO knockout (KO) mouse model. Results from micro-computed tomography (µCT) analysis of femur from 8-week-old 5-LO-deficient mice showed increased cortical bone and medullary region in females and males and decreased trabecular bone in females. In the vertebra, we observed increased marrow area in both females and males 5-LO KO and decreased trabecular bone only in females 5-LO KO. Immunohistochemistry (IHC) analysis showed higher levels of osteogenic markers tissue-nonspecific alkaline phosphatase (TNAP) and osteopontin (OPN) and lower expression of osteoclastogenic marker tartrate-resistant acid phosphatase (TRAP) in the femurs of 5-LO KO mice versus wild-type (WT). Alkaline phosphatase activity and mineralization assay results showed that the 5-LO absence enhances osteoblasts differentiation and mineralization but decreases the proliferation. Alkaline phosphatase (ALP), Bglap, and Sp7 gene expression were higher in 5-LO KO osteoblasts compared to WT cells. Eicosanoids production was higher in 5-LO KO osteoblasts except for thromboxane 2, which was lower in 5-LO-deficient mice. Proteomic analysis identified the downregulation of proteins related to adenosine triphosphate (ATP) metabolism in 5-LO KO osteoblasts, and the upregulation of transcription factors such as the adaptor-related protein complex 1 (AP-1 complex) in long bones from 5-LO KO mice leading to an increased bone formation pattern in 5-LO-deficient mice. We observed enormous differences in the morphology and function of osteoclasts with reduced bone resorption markers and impaired osteoclasts in 5-LO KO compared to WT osteoclasts. Altogether, these results demonstrate that the absence of 5-LO is related to the greater osteogenic profile. © 2023 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).
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Resorción Ósea , Osteogénesis , Masculino , Femenino , Ratones , Animales , Fosfatasa Alcalina/metabolismo , Microtomografía por Rayos X , Proteómica , Osteoclastos/metabolismo , Osteoblastos/metabolismo , Resorción Ósea/patología , Diferenciación Celular , Ratones Noqueados , Leucotrienos/metabolismo , Leucotrienos/farmacologíaRESUMEN
This study evaluated the effect of titanium tetrafluoride (TiF(4)) formulations on enamel carious demineralization in situ. Thirteen subjects took part in this cross-over, split-mouth, double-blind study performed in three phases of 14 d each. In each subject, two sound and two predemineralized specimens of bovine enamel were worn intra-orally and plaque accumulation was allowed. One sound and one predemineralized specimen in each subject was treated once with sodium fluoride (NaF) varnish or solution (Treatment A); TiF(4) varnish or solution (Treatment B); or placebo varnish or no treatment (Treatment C). The initially sound enamel specimens were exposed to severe cariogenic challenge (20% sucrose, eight times daily for 5 min each time), whereas the predemineralized specimens were not. Eleven subjects were able to finish all experimental phases. The enamel alterations were quantified by surface hardness and transversal microradiography. Demineralization of previously sound enamel was reduced by all test formulations except for the NaF solution, while both TiF(4) formulations were as effective as NaF varnish. For the predemineralized specimens, enamel surface hardness was increased only by TiF(4) formulations, while subsurface mineral remineralization could not be seen in any group. Within the experimental protocol, TiF(4) was able to decrease enamel demineralization to a similar degree as NaF varnish under severe cariogenic challenges, while only TiF(4) formulations remineralized the enamel surface.
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Cariostáticos/uso terapéutico , Caries Dental/prevención & control , Esmalte Dental/efectos de los fármacos , Fluoruros Tópicos/uso terapéutico , Fluoruro de Sodio/uso terapéutico , Titanio/uso terapéutico , Administración Tópica , Adulto , Análisis de Varianza , Cariostáticos/administración & dosificación , Estudios Cruzados , Caries Dental/fisiopatología , Método Doble Ciego , Femenino , Fluoruros Tópicos/administración & dosificación , Humanos , Masculino , Fluoruro de Sodio/administración & dosificación , Titanio/administración & dosificaciónRESUMEN
We compared the parameters related to glucose homeostasis, and liver and muscle proteomes in fluorosis-susceptible (A/J; S) and fluorosis-resistant (129P3/J; R) mice in response to fluoride (F) exposure and exercise. Ninety male mice (45 R-mice and 45 S-mice) were randomized into three groups: (SI; RI) No-F, No-Exercise, (SII; RII) 50 ppm F, No-Exercise, (SIII; RIII) 50 ppm F, Exercise. Overall, mean F concentrations in the plasma and femur were significantly higher in R-mice compared with S-mice. In R-mice, exercise resulted in an increase in F accumulation in the femur. In S-mice, the mean plasma glucose level was significantly higher in Group II compared with Groups I and III. There was an increase in liver proteins involved in energy flux and antioxidant enzymes in non-exercise groups (I, II) of S-mice in comparison with the corresponding groups of R-mice. The results also showed a decrease in muscle protein expression in Group I S-mice compared with their R-mice counterparts. In conclusion, the findings suggest an increased state of oxidative stress in fluorosis-susceptible mice that might be exacerbated by the treatment with F. In addition, fluorosis-susceptible mice have plasma glucose levels higher than fluorosis-resistant mice on exposure to F, and this is not affected by exercise.
RESUMEN
OBJECTIVE: The aim of this study was to determine whether there is a correlation between acid erosion and fluoride release of conventional glass ionomer cements. METHODS: Ten specimens for each material were prepared for fluoride release tests and five for acid erosion tests separately. After placed in pH cycling solution, concentration of fluoride was measured by a fluoride-ion selective electrode each day for 15 days. For the acid erosion test, specimens were immersed in a lactic acid solution and their depth measured with a spring-loaded dial gauge. The data were submitted to 3-way ANOVA, followed by Tukey's test (p<0.05) RESULTS: All materials showed ability to elute fluoride in the 15 day period of the test, with the same pattern of high fluoride release at the first 24h. Despite this, the amount of fluoride released was statistically different among the 18 groups, with the highest for Maxxion R and the lowest for Chemfil Rock (p>0.05). The highest acid erosion values were registered for Magic Glass, Ion Z, VitroFil and Maxxion R, which exceeded the maximum stipulated by the relevant ISO test (ISO 9917-1). A positive linear correlation (r2=0.4886) was found for both properties, i.e., higher fluoride release is related to higher acid erosion. SIGNIFICANCE: Acid erosion and fluoride release are related properties of GICs, though factors such as pH and P/L ratio lead to differences between actual values for individual brands of these materials.
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Fluoruros , Cementos de Ionómero Vítreo , Electrodos de Iones Selectos , Ensayo de MaterialesRESUMEN
The present study investigated the effect of chronic exercise on fluoride (F) metabolism in fluorosis-susceptible mice exposed to high-F and explored the relationship between F concentrations in bone and plasma. Thirty male mice were randomised into three groups: Group I (No-F, No-Exercise), Group II (50 ppmF, No-Exercise), Group III (50 ppmF, Exercise). Body weight and physical performance of all mice were measured at baseline and end of experiment. F concentrations of plasma and bone were measured at the end of experiment. Mean plasma F concentration was significantly higher (p < 0.001) in Groups II and III compared with Group I. Mean bone F concentration was also significantly higher (p < 0.01) in Groups II and III compared with Group I. There was a significant correlation (p = 0.01, r = 0.54) between F concentration of plasma and bone. Mean body weight of Group I mice was significantly higher than Group II (p < 0.001) and Group III (p = 0.001) mice at the end of the experiment. This study, which provides the first data on the effect of chronic exercise on F metabolism in fluorosis-susceptible mice, suggests no effect of chronic exercise on F in plasma and bone. However, exposure to high-F resulted in lower body weight and exercise capacity in mice.
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Fluoruros/metabolismo , Fluoruros/farmacología , Condicionamiento Físico Animal/fisiología , Animales , Peso Corporal/efectos de los fármacos , Huesos/química , Fluoruros/sangre , Fluorosis Dental , Masculino , Ratones , Rendimiento Físico FuncionalRESUMEN
OBJECTIVES: To determine the consumption of bottled water by children in the city of Bauru, State of São Paulo, Brazil. METHODS: A stratified sample of the 17 areas established by the city plan was used to identify a total of 1,000 homes for visitation. Information was collected using a questionnaire concerning the type of water consumed and population demographics. RESULTS: Overall, around 30 percent of all residences used bottled water. Among all households where bottled water was consumed, about 26 percent had children residing. For those with children and bottled water, 81 percent reported to use bottled water for the preparation of the children's foods and beverages. CONCLUSIONS: An important percentage of children consume bottled water in the city of Bauru, State of São Paulo, Brazil. Considering previous studies showing that fluoride concentrations vary in bottled water, public health measures should be implemented in order to guarantee adequate levels of fluoride in commercialized water.
Asunto(s)
Aguas Minerales/estadística & datos numéricos , Brasil , Cariostáticos/análisis , Niño , Fluoruros/análisis , Humanos , Aguas Minerales/análisis , Etiquetado de Productos , Clase Social , Encuestas y CuestionariosRESUMEN
The literature contains reports of the relationship between the fluoride concentrations in drinking water and human plasma. None of these studies, however, documented individual levels of daily fluoride intake, which can vary considerably among individuals served by the same water supply. Furthermore, while water can be an important source of fluoride, other sources, especially fluoridated dentifrices, also contribute substantially. This 2-day study with five 25-35-year-old subjects in each of three communities (Bauru, 0.6-0.8 ppm F; Domelia, 0.7 ppm F; Floresta, 0.3 ppm F) determined plasma fluoride concentrations and fluoride intake from diet and the use of dentifrice which, together, approximate total daily fluoride intake. The purposes were to determine: (1) the extent to which plasma fluoride concentrations approached levels known to affect the quality and quantity of bone; (2) the relationship between fluoride intake and plasma concentrations. Plasma was collected at 4-h intervals starting at 0800 h and ending at 2000 h each day. Average fluoride intakes from diet and the use of dentifrice in the three communities ranged from 0.16 to 0.82 mg/day and from 0.29 to 3.16 mg/day, respectively. The overall average plasma concentrations in the three communities were 0.44, 0.45 and 0.54 micromol/l (P<0.005). They were directly related to intake from the use of dentifrice (P=0.030) and to total intake (P=0.033), but were not related to dietary intake (P=0.176). In conclusion, despite fluoride intake from various sources, the plasma fluoride concentrations of the study subjects remained at levels far below those associated with effects on bone production.