Egr1 regulates the coordinated expression of numerous EGF receptor target genes as identified by ChIP-on-chip

UV stimulation of prostate cells causes an apoptotic response that is dependent on the zinc finger transcription factor Egr1; downstream targets of Egr1 in this response were identified

Understanding the roles of gingival beta-defensins

Gingival epithelium produces β-defensins, small cationic peptides, as part of its contribution to the innate host defense against the bacterial challenge that is constantly present in the oral cavity. Besides their functions in healthy gingival tissues, β-defensins are involved in the initiation and progression, as well as restriction of periodontal tissue destruction, by acting as antimicrobial, chemotactic, and anti-inflammatory agents. In this article, we review the common knowledge about β-defensins, coming from in vivo and in vitro monolayer studies, and present new aspects, based on the experience on three-dimensional organotypic culture models, to the important role of gingival β-defensins in homeostasis of the periodontium

Human ß defensin-1 and -2 expression in the gingiva of patients with specific periodontal diseases

PubMed ID: 17760820Background and Objective: ß defensin antimicrobial peptides are important in epithelial innate immunity, and their differential expression is associated with periodontal diseases. The aims of this study were to determine the mRNA expression of human ß defensin-1 and -2 in the gingival tissue of patients with gingivitis, aggressive periodontitis and chronic periodontitis, and to evaluate the relationship between defensin expression and type and/or severity of periodontal destruction. Material and Methods: Fifteen patients in each group with gingivitis, aggressive periodontitis and chronic periodontitis, and 10 healthy subjects, were included in the study (n = 55). The periodontal status of the subjects was determined by periodontal clinical measurements and radiographical evaluations. Transcriptional levels of human ß defensin-1 and -2 genes in gingival samples were assessed by using the quantitative real-time polymerase chain reaction technique, and the data were evaluated statistically by the relative expression Software Tool 2 for groupwise comparisons. Results: Expression of the human ß defensin-1 gene was lower in gingivitis and aggressive periodontitis groups, and significantly higher in the chronic periodontitis group, than in the control group (p < 0.001). Human ß defensin-2 mRNA expression in the gingivitis group was lower than in the control group; however, the difference was statistically significant only in half of the gingivitis patients (p < 0.001). Human ß defensin-2 mRNA levels were higher in some chronic periodontitis patients, but lower in the others when compared with the control group (p < 0.001). Expression of the human ß defensin-2 gene increased in the aggressive periodontitis group relative to the control group. Conclusion: This study suggests that human ß defensin-1 and -2 genes in the gingival epithelium show differential expression in patients with specific periodontal diseases, and aggressive and chronic periodontitis types demonstrate different gingival ß defensin-1 and -2 expression patterns. © 2007 The Authors

Systemic low-dose doxycycline and alendronate administration and serum interleukin-1beta, osteocalcin, and C-reactive protein levels in rats

Background: The aim of the present study was to evaluate the effects of systemic administration of low-dose doxycycline and a bisphosphonate, alendronate, on serum levels of interleukin-1β (IL-1β), osteocalcin (OC), and C-reactive protein (CRP) in experimental periodontitis in rats. Methods: Experimental periodontitis was induced by repeated injection of purified lipopolysaccharide (LPS) derived from Escherichia coli endotoxin. Forty-seven adult male Sprague-Dawley rats were divided into five study groups and given LPS, LPS + doxycycline, LPS + alendronate, LPS + doxycycline + alendronate, and saline control. At the end of the 1-week protocol, blood samples were obtained, and the rats were sacrificed. Serum samples were analyzed for IL-1β, OC, and CRP concentrations by enzyme-linked immunosorbent assay (ELISA). The jaws were defleshed, and alveolar bone loss was assessed morphometrically. Data were evaluated statistically by non-parametric tests. Results: Morphometric measurements revealed significantly more bone loss in the LPS group compared to the saline control group (P &#60;0.05). Alendronate revealed slight inhibition on alveolar bone loss either alone or in combination with doxycycline (alveolar bone loss: 0.41 mm in alendronate and combined drug treatment groups versus 0.45 mm in LPS and doxycycline groups). Significantly higher IL-1β levels were observed with alendronate either alone or in combination with doxycycline than in the LPS group (P &#60;0.05). Combined administration of doxycycline and alendronate showed significantly higher levels of OC than all of the other groups (P &#60;0.01). Serum CRP levels did not exhibit significant differences between the study groups. Conclusions: Alendronate either alone or in combination with doxycycline provided slight inhibition on LPS-induced alveolar bone resorption. The significantly increased serum OC level observed in the combined drug treatment group suggests that combined administration of alendronate and doxycycline might increase bone remodeling and thereby inhibit the progression of alveolar bone resorption in rats.</p