Cadmium-Induced Disruption in 24-h Expression of Clock and Redox Enzyme Genes in Rat Medial Basal Hypothalamus: Prevention by Melatonin

In a previous study we reported that a low daily p.o. dose of cadmium (Cd) disrupted the circadian expression of clock and redox enzyme genes in rat medial basal hypothalamus (MBH). To assess whether melatonin could counteract Cd activity, male Wistar rats (45 days of age) received CdCl2 (5 ppm) and melatonin (3 μg/mL) or vehicle (0.015% ethanol) in drinking water. Groups of animals receiving melatonin or vehicle alone were also included. After 1 month, MBH mRNA levels were measured by real-time PCR analysis at six time intervals in a 24-h cycle. In control MBH Bmal1 expression peaked at early scotophase, Per1 expression at late afternoon, and Per2 and Cry2 expression at mid-scotophase, whereas neither Clock nor Cry1 expression showed significant 24-h variations. This pattern was significantly disrupted (Clock, Bmal1) or changed in phase (Per1, Per2, Cry2) by CdCl2 while melatonin counteracted the changes brought about by Cd on Per1 expression only. In animals receiving melatonin alone the 24-h pattern of MBH Per2 and Cry2 expression was disrupted. CdCl2 disrupted the 24-h rhythmicity of Cu/Zn- and Mn-superoxide dismutase (SOD), nitric oxide synthase (NOS)-1, NOS-2, heme oxygenase (HO)-1, and HO-2 gene expression, most of the effects being counteracted by melatonin. In particular, the co-administration of melatonin and CdCl2 increased Cu/Zn-SOD gene expression and decreased that of glutathione peroxidase (GPx), glutathione reductase (GSR), and HO-2. In animals receiving melatonin alone, significant increases in mean Cu/Zn and Mn-SOD gene expression, and decreases in that of GPx, GSR, NOS-1, NOS-2, HO-1, and HO-2, were found. The results indicate that the interfering effect of melatonin on the activity of a low dose of CdCl2 on MBH clock and redox enzyme genes is mainly exerted at the level of redox enzyme gene expression

Píldoras de aprendizaje: Vídeos de corta duración en la docencia del Grado de Medicina

Los mini-vídeos pueden ser considerados píldoras de aprendizaje (llamadas píldoras de conocimiento), ya que durante su visionado se accede rápidamente a una información concreta, cuya única finalidad es reforzar otros materiales didácticos, mejorar la comprensión de los contenidos de la asignatura y aumentar la motivación de los estudiantes. Dado los beneficios del uso de estos recursos didáctico, un grupo de profesores de la Facultad de Medicina, una investigadora del Área de Ciencias de la Salud y un Médico del Servicio de Medicina Intensiva del Hospital Clínico San Carlos diseñaron mini-vídeos para utilizarlos en la docencia de la asignatura de Bioquímica Humana de segundo curso del Grado de Medicina. La preparación de cada mini-vídeo ha supuesto un arduo trabajo tanto en la elaboración como en el diseño de los elementos que integran cada recurso audiovisual. Sin embargo, el resultado ha sido muy satisfactorio tanto para los estudiantes como para los docentes que participaron en esta experiencia

¿Es útil Google Sites en la enseñanza Universitaria del Área de Ciencias de la Salud?

La elaboración de una página Web dentro del ámbito de la educación permite el diseño de una Recurso Educativo Abierto que podría estar englobado dentro de la metodología Flipped learning o clase invertida. Por ello, un grupo de profesores de la Facultad de Medicina y profesiones del ámbito de la Medicina y Odontología han elaborado un entorno formativo on-line específico, mediante la herramienta Google Sites, en una materia de conocimiento, como Bioquímica y Genética Molecular durante el curso 2019/2020. Esta página web se ha empleado en distintas asignaturas y ha facilitado la adquisición de algunas competencias que son comunes en distintas titulaciones universitarias

Aplicación de la WebQuest en la enseñanza universitaria del área de Ciencias de la Salud

El presente proyecto es una propuesta para evaluar el uso de la WebQuest en la docencia de la asignatura de Bioquímica Humana durante el curso 2018-2019. Esta actividad de investigación es una estrategia de aprendizaje que fomenta la adquisición de habilidades como el análisis, la integración de conocimientos, la capacidad de resolución de problemas y el aprendizaje cooperativo, por lo que podría ser útil para la docencia del área de ciencias de la salud

Effect of cadmium on lymphocyte subsets distribution in thymus and spleen

This work was designed to analyze the possible dose dependent effects of cadmium on the distribution of lymphocyte subsets within the thymus and spleen. Cadmium accumulation was also evaluated in these tissues. For this purpose, adult male rats were exposed for one month to 0, 5, 10, 25, 50 or 100 ppm of cadmium chloride (CdCl2) in the drinking water. In both spleen and thymus, the B lymphocytes increased with the doses of 5 and 10 ppm of CdCl2, and decreased with the doses of 25-100 ppm. In spleen, the doses of 25 and 50 ppm decreased CD4+ cells and the doses of 5 and 10 ppm increased CD8+ cells, while the percentage of Thymus T, CD4+, CD8+ and CD4+-CD8+ cells was not modified by cadmium treatment at any dose used in this study. After cadmium exposure, the metal was accumulated in the spleen only from the dose of 50 ppm on, and in the thymus, from the dose of 10 ppm on. In conclusion, although the accumulation of the metal is higher in thymus than in spleen, the metal affected CD4+ and CD8+ lymphocytes at the spleen but not at the thymusEn este trabajo se analizan los posibles efectos inducidos por la exposición al cadmio sobre las subpoblaciones linfocitarias en bazo y timo y se evalúa la acumulación del metal en estos tejidos. Para ello, se tratan ratas macho adultas durante un mes con cloruro de cadmio (CdCl2) en el agua de bebida a dosis de 0, 5, 10, 25, 50 y 100 ppm. En las ratas tratadas con 5 y 10 ppm de CdCl2, el porcentaje de linfocitos B aumenta en bazo y timo, descendiendo a partir de la dosis de 25 ppm, en ambos tejidos. En bazo de ratas expuestas a las dosis de 25 y 50 ppm, el porcentaje de linfocitos CD4+ desciende, mientras que a las dosis de 5 y 10 ppm, aumenta el porcentaje de células CD8+. Tras la exposición al cadmio, el porcentaje de linfocitos T, CD4+, CD8+ y CD4+-CD8+ no varía en el timo con ninguna de las dosis administradas en este estudio. En las ratas tratadas, el cadmio se acumula en el bazo a partir de la dosis de 50 ppm, mientras que en el timo, lo hace a partir de la dosis de 10 ppm. Estos resultados indican, por tanto, que aunque la acumulación de cadmio es mayor en timo que en bazo, este metal afecta a la proporción de linfocitos CD4+ y CD8+ en el bazo pero no en el tim

Optimization of buffer solutions to analyze inflammatory cytokines in gingival crevicular fluid by multiplex flow cytometry

Objective: the aim of this study was to test two buffer solutions in order to attain a reliable and reproducible analysis of inflammatory cytokines (IL-1β, IL-6, TNF-α, OPG, OPN and OC), in gingival crevicular fluid (GCF) by flow cytometry. Material and Methods: GCF samples from healthy volunteers were collected with perio-paper strips and diluted either in phosphate buffered saline (PBS) or Tris-HCl buffer, with and without protease inhibitors (PI). Cytokine immunoassays were carried out by flow cytometry (Luminex Xmap 200 ) generating standard curves. Results: standards curves generated with the use of phosphate-buffered saline (PBS) demonstrated best adjustment for cytokines IL-1ß, IL-6 and TNF- α levels, when using Tris-HCl ( p <0.05). Conclusions: The use of PBS buffer with the addition of PI provided reliable measurements of inflammatory biomarkers in GCF samples of healthy volunteers

Melatonin as adjunctive therapy in the treatment of periodontitis associated with obesity

Aims To study the effect of adjunctive systemic administration of melatonin to standard mechanical periodontal therapy in obese rats with experimental periodontitis. Materials and methods In 42 Wistar rats with an initial body weight of 180 g., half (n=21) were fed with a high‐fat diet to induce obesity. In both obese and normal‐weight groups, experimental periodontitis was subsequently induced through oral gavages with a combination of Porphyromona gingivalis and Fusobacterium nucleatum. Both groups were randomly allocated to either, no treatment or periodontal treatment consisting on standard mechanical debridement, with either adjunctive chlorhexidine or melatonin. Outcomes were evaluated by the changes in clinical parameters (probing depth modified gingival index, plaque dental index and bleeding on probing), in bone resorption and in the levels of biomarkers in plasma and in gingival tissue (inflammatory cytokines, insulin, leptin, osteocalcin, osteopontin, plasminogen activator inhibitor‐1, intercellular adhesion molecule 1, E‐selectin and lipids). Results In the obese‐periodontitis group, adjunctive melatonin administration resulted in reduced gingival inflammation and bleeding on probing, with significant reductions in probing depth and enhanced bone repair demonstrated by Micro‐CT (15% reduction in alveolar bone destruction) when compared with the same group treated with adjunctive CHX or the normal‐weight rats with either melatonin or CHX. In this melatonin‐treated obese‐periodontitis group, a significant impact on biochemical biomarkers was also demonstrated in both gingival and plasma samples, when compared with the other groups, with significant reductions in pro‐inflammatory cytokines. Conclusions Adjunctive melatonin therapy significantly reduced alveolar bone loss and exerted a protective anti‐inflammatory effect mainly in those experimental animals affected by the co‐morbidity of periodontitis and obesity

Melatonin expression in periodontitis and obesity: An experimental in-vivo investigation

Background and Objective: Melatonin deficiency has been associated with obesity and systemic inflammation. This study aims to evaluate whether melatonin could interfere with the mechanisms of co‐morbidity linking obesity and periodontitis. Material and Methods: Twenty‐eight male Wistar rats were randomly divided in 4 groups: control group (Con) (fed with standard diet); high‐fat diet group (HFD) (fed with a diet containing 35.2% fat); Con group with induced periodontitis (Con‐Perio) and HFD group with induced periodontitis (HFD‐Perio). To induce periodontitis, the method of oral gavages with Porphyromonas gingivalis ATCC W83K1 and Fusobacterium nucleatum DMSZ 20482 was used. Circulating melatonin levels were analyzed by multiplex immunoassays. Periodontitis was assessed by alveolar bone loss (micro‐computed tomography and histology) and by surrogate inflammatory outcomes (periodontal pocket depth, modified gingival index and plaque dental index). Results: Plasma melatonin levels were significantly decreased (P < .05) in the obese rats with periodontitis when compared with controls or with either obese or periodontitis rats. Alveolar bone loss increased 27.71% (2.28 µm) in HFD‐Perio group compared with the Con group. The histological analysis showed marked periodontal tissue destruction with osteoclast activity, particularly in the HFD‐Perio group. A significant negative correlation (P < .05) was found between periodontal pocket depth, modified gingival index and circulating melatonin levels. Conclusion: Obese and periodontitis demonstrated significantly lower melatonin concentrations when compared with controls, but in obese rats with periodontitis these concentrations were even significantly lower when compared with either periodontitis or obese rats. These results may indicate that melatonin deficiency could be a key mechanism explaining the co‐morbidity effect in the association between obesity and periodontitis. © 2018 Wile

Citrus essential oils inhalation by mice: Behavioral testing, GCMS plasma analysis, corticosterone, and melatonin levels evaluation

Issue Online: 11 January 2018 Version of Record online: 23 November 2017 Manuscript accepted: 03 October 2017 Manuscript revised: 30 September 2017 Manuscript received: 02 August 2016The use of orange essential oils (EOs) as a complementary treatment is very common in Brazilian popular culture. The levels of melatonin (MEL) and corticosterone (CORT) hormones were investigated simultaneously, by the Luminex™ immunoassay system in mice plasma, after Citrus aurantium and Citrus sinensis EOs inhalation for 30 min. The plasma was analyzed by headspace through gas chromatography coupled to mass spectrometry for investigation of the EO components. Mice were submitted to behavioral testing to research anxiolytic-like, sedative, and antidepressant-like effects. The inhalation of atmosphere obtained from vaporization of 10% solution of this Citrus EO separately did not affect MEL or CORT plasma levels; that is, the MEL and CORT levels did not present variation in function of the EO in the schedule used. On the other hand, the imipramine positive control used altered the level of MEL as expected. The EO constituents were detected in plasma at different ratios that is present in inhaled EO. Behavioral tests showed that the inhalation of 10% C. sinensis EO presents an anxiolytic-like and sedative effect. Thus, C. sinensis EO can be a valuable tool for treatment of the anxiety disturbs, apparently without interference with MEL and CORT physiological levels.Consejo Nacional de Desarrollo Científico y Tecnológico (CNPq) (Brasil)Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul (FAPERGS) (Brasil)Depto. de Bioquímica y Biología MolecularFac. de MedicinaTRUEpu

Obesity and periodontitis: An experimental study to evaluate periodontal and systemic effects of comorbidity

Issue Online: 01 March 2018 Version of Record online: 16 February 2018 Manuscript accepted: 03 August 2017 Manuscript received: 09 June 2017Background: Obesity and overweight have been associated with periodontitis. This study aims to evaluate periodontal and systemic effects of this association in a validated experimental model. Methods: Twenty-eight male Wistar rats were randomly divided into four groups: 1) control group (Con) (fed with standard diet); 2) high-fat diet group (HFD) (fed with a diet containing 35.2% fat); 3) control group with induced periodontitis (Con-Perio); and 4) HFD group with induced periodontitis (HFD-Perio). To induce periodontitis, oral gavages with Porphyromonas gingivalis ATCC W83K1 and Fusobacterium nucleatum DMSZ 20482 were used. Periodontal outcomes were evaluated by inflammatory parameters, periodontal probing depth (PD), and modified gingival index (MGI). Systemic effects were evaluated by measuring levels of inflammatory cytokines, insulin, adiponectin, and leptin using multiplex immunoassays and levels of visfatin, resistin, lipid profiles, transaminases, and plasma endotoxin using colorimetric tests and the glucose tolerance test. Results: Clinical parameters (PD and MGI) were significantly increased (P < 0.05) in the induced periodontitis groups compared with controls. The HFD-Perio group demonstrated significantly higher PD compared with Con-Perio group. Lipid profiles, cytokines, and adipocytokines showed significantly elevated levels in the HFD-Perio group compared with the other groups. Similarly, glucose levels in the HFD-Perio group were significantly higher (P < 0.05) than in the HFD group, and hepatic damage parameters demonstrated a tendency toward higher levels in the HFD-Perio group. Conclusion: Obesity and periodontitis demonstrated a comorbidity effect on both systemic inflammatory and metabolic dysregulation biomarkers, with increased glucose, dyslipidemia and hepatic damage.Depto. de Especialidades Clínicas OdontológicasDepto. de Bioquímica y Biología MolecularDepto. de Biología CelularFac. de OdontologíaFac. de MedicinaTRUEpu