Clinical trial NCT03371446: DNA Methylation Profile of the SOCS-1 Gene Promoter in Smokers Patients With Chronic Periodontitis.
Official title: Effect of Smoking on the DNA Methylation Profile of the SOCS 1 Gene Promoter in Oral Mucosal Epithelial Cells of Individuals With Chronic Periodontitis (Smokers and Nonsmokers).
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Periodontal Diseases
Epigenetics
Keywords: DNA Methylation. Smoking. SOCS-1 gene.
Lead sponsor: University of Sao Paulo
Sponsor class: OTHER
First posted: 2017-12-13
Enrollment: 60
Sex: ALL
Minimum age (years): 30
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Observational model: CASE_CONTROL
Time perspective: OTHER
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Patients who smoked for more than 10 years, consuming 10 more cigarettes per day and diagnosing chronic periodontitis (case) and another group (control) were non-smokers with chronic periodontitis, according to the standard of WHO definition of the smoking population,The ChP was diagnose in accordance with the recommended standards from the Center for Disease control and Prevention, the American Academy of Periodontology on the condition of patients in good general health, aged over 30 years, presenting with pocket periodontal disease with CAL ≥ 5 mm and radiographic bone loss and bleeding after probing.

Brief summary: Periodontitis is related to host genetics, constitution of the dental biofilm and environmental factors such as smoking. DNA methylation is a mechanism of genetic expression that can inhibit or silence gene expression. In this way several researchers have been dedicated to study the genetic influence on the susceptibility and / or increased risk to periodontal disease. Studies have reported association between several epigenetic biomarkers with periodontal inflammation. Considering the hypothesis that there is an association between smoking and methylation in genes related to periodontal disease, the objective of this study was to verify the DNA methylation pattern in oral epithelial cells of patients with chronic periodontitis (CP) in the promoter of a specific gene involved in the control of inflammation, as suppressor of cytokine signaling (SOCS) 1 in smokers and nonsmokers patients.

Detailed description: This was an experimental type study with parallel controls, comparing two groups, a group with consumption of 10 minimum cigarettes per day, with a diagnosis of chronic periodontitis. And another control group were non-smokers with chronic periodontitis. For this, genomic DNA was purified from oral epithelial cells obtained by rinsing with 3% sucrose, for a single time of collection, patients received periodontal treatment after collection and data analysis. The DNA was modified by Sodium bisulfite and the methylation patterns of the DNA were analyzed with the MSPCR technique (Polymerase chain reaction). This study was approved by the Institutional Review Board of the School of Dentistry of Ribeirão Preto (CAAE:57171816.2.0000.5419 ), and all patients need to provide written informed consent.

Eligibility criteria: Inclusion Criteria:

* Chronic Periodontitis carriers - presence of proximal insertion loss ≥5 mm in more than 30% of the teeth present.
* Periodontal pocket ≥ 5mm
* Smokers who have smoked 10 or more cigarettes per day for the past five years.
* No positive history of basic periodontal treatment in the last six months.

Exclusion Criteria:

* Extensive prosthetic involvement.
* Using anti-inflammatories.
* Pregnant or nursing.
* Presence of systemic alterations that compromise host response or require prophylactic medication for treatment.
* History of constant use of oral antiseptics in the last six months.

Primary outcomes:
measure: Extraction of genomic DNA from oral epithelial cells
timeFrame: Baseline (at the beginning of the study)
Secondary outcomes:
measure: Probing pocket depth (PD)
timeFrame: Baseline (at the beginning of the study)
measure: Plaque index (PI)
timeFrame: Baseline (at the beginning of the study)
measure: Bleeding on probing (BOP)
timeFrame: Baseline (at the beginning of the study)
Other outcomes:
Locations:
city: Ribeirão Preto
country: Brazil
facility: Arthur Belem Novaes Junior
state: SP
Study officials:
affiliation: Study Principal Investigator
name: Arthur B. Novaes Junior, DDS, PhD
role: PRINCIPAL_INVESTIGATOR
References: