Identifikation Parodontitis spezifischer microRNAs

Parodontitis ist eine Entzündung des Zahnhalteapparates. Dabei bewirkt das Wechselspiel zwischen entzündungsverursachenden Bakterien und Abwehrreaktionen des Organismus eine irreversible Gewebedestruktion. Einige Studien zeigten eine Beteiligung von microRNAs an den pathologischen Prozessen bei oralen Erkrankungen. Ein Ziel dieser Studie war es, microRNAs zu identifizieren, die bei der Parodontitis vermehrt ins Blut gelangen und die Zielgene der regulatorischen Effekte einer ausgewählten microRNA zu identifizieren, die ebenfalls im Zahnfleisch von Parodontitis Patienten angereichert ist. Das Blut von 18 Parodontitispatienten und 70 gesunden Kontrollen wurde unter Verwendung des Geniom Biochip-Arrays untersucht und dabei wurden 863 microRNAs quantifiziert. Um Zielgene der microRNA-Regulation zu identifizieren, wurden mirVana-miRNA-Mimetika in primären gingivalen Fibroblasten (pGFs) von drei unabhängigen Spendern überexprimiert. Das genomweite Expressionsprofil wurde in drei biologischen Replikaten unter Verwendung des Clariom D Expression Array durchgeführt.Die Spezifität der microRNA-abhängigen Regulation wurde unter Verwendung eines Reportergen-Assays und Luciferase-Aktivität in HeLa-Zellen validiert. Drei microRNAs zeigten eine unterschiedliche Expression in Blut von Parodontitis-Fällen im Vergleich zu dem Blut von gesunden Kontrollen. hsa-miR-374b-5p hat in zwei unabhängigen microRNA-Expressionsstudien eine mehr als 2-fache Erhöhung in Zahnfleisch bei Parodontitis-Fällen gezeigt. Expressionsprofile in gingivalen Fibroblasten, die mit microRNA-Mimetikum miR-374b-5p transfiziert wurden, haben das Gen UHMK1 als Zielgen der hsa-miR-374b-5p-Regulation nachgewiesen. Dieses Gen spielt eine Rolle bei der Regulation der Homöostase von Osteoblasten und Osteoklasten

hsa‐miR‐374b‐5p regulates expression of the gene U2AF homology motif (UHM) kinase 1

Objective: We aimed to identify a microRNA (miRNA) that is significantly upregulated in blood and in cells of the oral mucosa upon exposure to the periodontitis main risk factors oral inflammation and tobacco smoke, to subsequently identify its target gene and to describe the molecular mechanism of gene regulation. Background: miRNAs are associated with many disorders. Array-based miRNA expression studies indicated a number of differentially expressed miRNAs in the pathology of oral diseases. However, these miRNAs mostly lacked replication, and their target genes have remained unknown. Methods: 863 miRNAs were analyzed in blood from 18 PD cases and 70 controls (Geniom Biochip). Selected miRNAs were analyzed for upregulation in the inflamed oral mucosa of PD patients using published miRNA expression profiling studies from gingival cells. hsa-miR-374b-5p mimic was overexpressed in primary gingival fibroblasts (pGFs) from 3 donors, and genome-wide mRNA expression was quantified (Clarion Array). Gene-specific regulation was validated by qRT-PCR and Luciferase activity in HeLa cells. Results: hsa-miR-374b-5p showed >twofold change (FC) in 3 independent studies performed in blood, gingival tissues, and cells. After hsa-miR-374b-5p overexpression, genome-wide expression analysis showed UHMK1 as top 1 downregulated gene in pGFs (p = 2.5 × 10-04 , fold change = -1.8). Reporter genes demonstrated that hsa-miR-374b-5p downregulates mRNA levels (p = .02; FC = -1.5), leading to reduction in protein activity (p = .013, FC = -1.3). Conclusions: hsa-miR-374b-5p is upregulated in blood and ginvial cells exposed to oral inflammation and tobacco smoke and regulates UHMK1, which has a role in osteoclast differentiation

The COVID-19 pandemic and its global effects on dental practice : An International survey

Objectives: A multicentre survey was designed to evaluate the impact of COVID-19 outbreak on dental practice worldwide, estimate the COVID-19 related symptoms/signs, work attitudes and behaviour and the routine use of protective measures and Personal Protective Equipment (PPE). Methods: A global survey using a standardized questionnaire with research groups from 36 countries was designed. The questionnaire was developed and pretested during April 2020 and contained three domains: 1) Personal data; 2) COVID-19 positive rate and symptoms/signs presumably related to the coronavirus; 3) Working conditions and PPE adopted after the outbreak. Countries' data were grouped by the Country Positive Rate (CPR) during the survey period and by Gross-National-Income per capita. An ordinal multinomial logistic regression model was carried out with COVID-19 self-reported rate referred by dental professionals as dependent variable to assess the association with questionnaire items. Results: A total of 52,491 questionnaires were returned with a male/female ratio of 0.63. Out of the total respondents, 7,859 dental professionals (15%) reported symptoms/signs compatible with COVID-19. More than half of the sample (n = 27,818; 53%) stated to use FFP2/N95 masks, while 21,558 (41.07%) used eye protection. In the bivariate analysis, CPR and N95/FFP2 were significantly associated (OR = 1.80 95% =5.20 95% 95% CI = 1.60/2.82 and OR CI = 1.44/18.80, respectively), while Gross-National-Income was not statistically associated with CPR (OR = 1.09 CI = 0.97/1.60). The same significant associations were observed in the multivariate analysis. Conclusions: Oral health service provision has not been significantly affected by COVID-19, although access to routine dental care was reduced due to country-specific temporary lockdown periods. While the dental profession has been identified at high-risk, the reported rates of COVID-19 for dental professionals were not significantly different to those reported for the general population in each country. These findings may help to better plan oral health care for future pandemic events