Doxycycline restores the impaired osteogenic commitment of diabetic-derived bone marrow mesenchymal stromal cells by increasing the canonical WNT signaling.

Diabetes mellitus comprehends a group of chronic metabolic disorders, associated with damage and dysfunction of distinct tissues, including bone. At the cellular level, an impaired osteoblastogenesis has been reported, affecting the viability, proliferation and functionality of osteoblasts and precursor populations, hampering the bone metabolic activity, remodeling and healing. Tetracyclines embrace a group of broad-spectrum antibacterial compounds with potential anabolic effects on the bone tissue, through antibacterial-independent mechanisms. Accordingly, this study aims to address the modulatory capability and associated molecular signaling of a low dosage doxycycline - a semi-synthetic tetracycline, in the functional activity of osteoblastic progenitor cells (bone marrow-derived mesenchymal stromal cells), established from a translational diabetic experimental model. Bone marrow-derived mesenchymal stromal cells were isolated from streptozotocin-induced diabetic Wistar rat with proven osteopenia. Cultures were characterized, in the presence of doxycycline (1 µg ml-1) for proliferation, metabolic activity, apoptosis, collagen synthesis and relevant gene expression with the osteogenic and adipogenic program. The activation of the Wnt/ß-catenin pathway was further detailed. Doxycycline normalized the viability, proliferation and metabolic activity of the established cultures, further decreasing cell apoptosis, to levels similar to control. The addition of this drug to the culture environment further increased the osteogenic activation, upregulating the expression of osteogenic markers and collagen synthesis, at the same time that a decreased adipogenic priming was attained. These processes were found to me mediated, at least in part, by the restoration of the signaling through the Wnt/ß-catenin pathway.

Influência do estresse esportivo na inflamação gengival / The influence of physical stress on gingival inflammation

Objetivo: O estudo propõe avaliar a relação potencial entre o estresse desportivo, medido pelos níveis decortisol salivar, e a doença periodontal, e comparar em praticantes de natação, em percurso de alta competição,o status periodontal com indivíduos da mesma faixa etária não atletas. Materiais e métodos: Foramrealizadas duas coletas de saliva (matinal e vespertina) em 58 atletas e 47 não atletas para quantificaçãodo cortisol salivar determinado por rádio-imunoensaio e expressa em nmol/L. Em cada participante, foiavaliada a hemorragia gengival pelo Gingival Bleeding Index (Ainamo & Bay) e foram quantificados os níveisde placa pelo método de O´Leary, Drake & Naylor, com base em quatro pontos por dente (mesial, distal,vestibular, lingual/palatino). Resultados: Foi realizada uma análise bivariada para determinar potenciaisassociações entre variáveis e diferenças entre grupos. Conclusão: Em relação ao controle, os praticantes denatação em percurso de alta competição apresentam níveis de cortisol e inflamação gengival mais elevadose níveis de placa semelhantes. Assim, existe a necessidade de adoção de cuidados preventivos orientadospara a gengivite nos indivíduos que, pelas suas ocupações, estão sujeitos a níveis elevados de cortisol.

Objective: The study aims to evaluate the potential link between sports stress, measured by salivary cortisollevels, and periodontal disease, and compare the periodontal status of swimmers in the route of high competitionwith same-age individuals who are non-athletes. Materials and methods: 58 athletes and 47 non-athleteswere evaluated. Two samples of saliva were taken (morning and evening) for quantification of the levels of cortisolwhich were determined by radio-immunoassay and expressed in nmol/L. The Gingival Bleeding Index byAinamo & Bay and the levels of plaque determined by the O´Leary, Drake & Naylor method were both measuredon four points per tooth (mesial, distal, buccal, lingual/palatal) in each participant. Results: We performed abivariation analysis to determine potential associations between variables and differences between groups.Conclusion: Swimmers of high competition level show greater levels of cortisol and higher gingival inflammation,with plaque levels similar to control, than non-swimmers. On this way, there is a need for the adoption ofpreventive care towards gingivitis in individuals subject to high levels of cortisol by their occupations.

[Periodontal disease, tobacco and preterm delivery]. / Doença periodontal, tabaco e parto pré-termo.

Preterm delivery is associated with high mortality and morbility perinatal, being the costs dispended by the family and the National Health System with preterm newborns extremely high. However, it has been difficult to reduce its incidence due to the various factors involved. There is scientific evidence which support the relationship between periodontal disease and preterm delivery. There is also evidence of tobacco as a risk factor for periodontal disease, even though the relationship with preterm delivery is not yet clear. The aims of our study were to evaluate, in women in a post-partum period, dental and periodontal status as well as the exposure to tobacco and to establish the relationship between these two factors with preterm delivery. We performed a case control study with 237 parturient women from the Department of Obstetrics and Gynecology of Hospital S. João, E.P.E., during the first 48 hours after birth. A total of 86 gave birth at a gestational age under 37 weeks (case group ) and 151 gave birth to term newborns with birthweight equal or superior 2500 g (control group). The prevalence of some indicators of periodontal disease in the studied population was extremely high, namely gingival inflammation and gingival recession, and more of 30% had values of probing depth equal or higher than 4 mm significantly. Based on these periodontal indicators, only the presence of recession in more than two teeth seems to increase the risk of preterm delivery in fivefold (OR = 5,28; IC95%: 1,63-17,04). There is a statistically significant association between probing depth equal or higher than 4mm and smoking during pregnancy. This association might be relevant because 20% of preterm newborns mothers smoked during pregnancy and the proportion that stopped smoking during pregnancy in this group of mothers was almost half of the number of the control group. Therefore it is necessary to embody the information about this thematic in the health education, not only in pregnant women but in the general population, alerting for the smoking influence in periodontal disease, in pregnant women and in newborns. Interventions to help pregnant women to stop smoking should be included, not only in prenatal care guidelines used in hospitals, but also by dental medicine providers.