Circadian Clock Gene Expression in Periodontal Disease

NCT07452783 | Completed

• 2 other identifiers: IUCREC.2024/05.13TDH-2024-3463
• Study Type: observational
• Target: 60
• Locations: 1 country
• Sites: 1

Brief Summary

This observational study aims to investigate whether periodontal inflammation is associated with alterations in the expression of circadian clock-related genes and proteins in gingival tissues. Circadian rhythms regulate many biological processes, including immune responses and inflammation. Although experimental studies suggest a link between circadian disruption and periodontal disease, human data under controlled chronotype conditions are limited. A total of 60 systemically healthy, non-smoking individuals aged 22-45 years with comparable sleep patterns (intermediate chronotype and 6-9 hours of sleep) were included. Participants were classified as periodontally healthy, gingivitis, or stage III grade B periodontitis according to established diagnostic criteria. Gingival tissue samples were collected during clinically indicated procedures within a standardized morning time window (09:00-11:00). Gene expression levels of circadian clock components (CLOCK, BMAL1, PER1-3, CRY1-2, Rev-Erb-β, ROR-α) and inflammatory mediators (IL-1β, IL-6, TNF-α, NF-κB, IFN-γ, RANKL, OPG) were analyzed using RT-qPCR, Western blot, and ELISA techniques. Associations between molecular findings and clinical periodontal parameters were evaluated. The study seeks to clarify whether periodontal disease itself may disrupt local circadian regulatory mechanisms in gingival tissues.

Conditions

Gingivitis; Periodontitis

Keywords

Circadian Rhythm; BMAL1; CLOCK; Per1; Per2; Per3; CRY1; CRY2; ROR-α; Rev-Erb-β; IL-1β; IL-6; TNF-α; IFN-γ; RANKL; OPG; NF-κB; Periodontitis; Inflammation

Outcome Measures

Primary Outcomes (1)

• Relative mRNA Expression Levels of Circadian Clock Genes in Gingival Tissue

  Quantitative assessment of BMAL1, CLOCK, PER1, PER2, PER3, CRY1, CRY2, REV-ERBβ, and ROR-α mRNA expression levels in gingival tissue samples using real-time quantitative polymerase chain reaction (RT-qPCR). Expression levels will be calculated as relative fold changes normalized to housekeeping genes and compared among periodontally healthy, gingivitis, and Stage III Grade B periodontitis groups.

  At the time of gingival tissue collection (single time point)

Secondary Outcomes (3)

• Pro-inflammatory Cytokine Expression Levels

  At the time of tissue collection

• NF-κB Expression Level

  At the time of tissue collection

• Bone Metabolism Markers

  At the time of tissue collection

Study Arms (3)

Periodontally Healthy

Systemically healthy individuals with clinically healthy periodontal tissues, no attachment loss, and no radiographic bone loss.

Procedure: Gingival Tissue Biopsy

Gingivitis

Systemically healthy individuals presenting with gingival inflammation without clinical attachment loss or radiographic bone loss.

Procedure: Gingival Tissue Biopsy

Stage III Grade B Periodontitis

Systemically healthy individuals diagnosed with Stage III Grade B periodontitis according to the 2018 classification of periodontal diseases.

Procedure: Gingival Tissue Biopsy

Interventions

Gingival Tissue Biopsy PROCEDURE

Collection of gingival tissue samples from interproximal sites during clinically indicated periodontal procedures for molecular and protein expression analyses.

Gingivitis; Periodontally Healthy; Stage III Grade B Periodontitis

Eligibility Criteria

• Age: 25 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Systemically healthy adult individuals seeking care at the Department of Periodontology, Inonu University Faculty of Dentistry, were recruited. Participants were categorized into three groups based on periodontal status: periodontally healthy, gingivitis, and Stage III Grade B periodontitis according to the 2018 classification of periodontal diseases. All participants required clinically indicated periodontal procedures from which gingival tissue samples could be obtained.

You may qualify if:

• Adults aged 18 years or older
• Systemically healthy individuals
• Presence of at least 20 natural teeth
• Individuals classified as periodontally healthy, gingivitis, or Stage III Grade B periodontitis according to the 2018 classification of periodontal diseases
• Willingness to provide written informed consent

You may not qualify if:

• Presence of any systemic disease affecting periodontal status (e.g., diabetes mellitus, autoimmune diseases, cardiovascular diseases)
• Use of antibiotics or anti-inflammatory medications within the previous 3 months
• Periodontal therapy within the last 6 months
• Current smokers or individuals who quit smoking within the past 5 years
• Pregnancy or lactation
• Use of medications known to influence immune or inflammatory responses
• History of systemic conditions that may affect wound healing

Sponsors & Collaborators

• Inonu University: lead

Study Sites (1)

Inonu University Faculty of Dentistry

Malatya, 44210, Turkey (Türkiye)

Location

Related Publications (6)

• Kapila YL. Oral health's inextricable connection to systemic health: Special populations bring to bear multimodal relationships and factors connecting periodontal disease to systemic diseases and conditions. Periodontol 2000. 2021 Oct;87(1):11-16. doi: 10.1111/prd.12398.

  PMID: 34463994 BACKGROUND

• Chapple ILC, Mealey BL, Van Dyke TE, Bartold PM, Dommisch H, Eickholz P, Geisinger ML, Genco RJ, Glogauer M, Goldstein M, Griffin TJ, Holmstrup P, Johnson GK, Kapila Y, Lang NP, Meyle J, Murakami S, Plemons J, Romito GA, Shapira L, Tatakis DN, Teughels W, Trombelli L, Walter C, Wimmer G, Xenoudi P, Yoshie H. Periodontal health and gingival diseases and conditions on an intact and a reduced periodontium: Consensus report of workgroup 1 of the 2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions. J Periodontol. 2018 Jun;89 Suppl 1:S74-S84. doi: 10.1002/JPER.17-0719.

  PMID: 29926944 BACKGROUND

• Dibner C, Schibler U, Albrecht U. The mammalian circadian timing system: organization and coordination of central and peripheral clocks. Annu Rev Physiol. 2010;72:517-49. doi: 10.1146/annurev-physiol-021909-135821.

  PMID: 20148687 BACKGROUND

• Hergenhan S, Holtkamp S, Scheiermann C. Molecular Interactions Between Components of the Circadian Clock and the Immune System. J Mol Biol. 2020 May 29;432(12):3700-3713. doi: 10.1016/j.jmb.2019.12.044. Epub 2020 Jan 10.

  PMID: 31931006 BACKGROUND

• Hastings M, O'Neill JS, Maywood ES. Circadian clocks: regulators of endocrine and metabolic rhythms. J Endocrinol. 2007 Nov;195(2):187-98. doi: 10.1677/JOE-07-0378.

  PMID: 17951531 BACKGROUND

• Czeisler CA, Duffy JF, Shanahan TL, Brown EN, Mitchell JF, Rimmer DW, Ronda JM, Silva EJ, Allan JS, Emens JS, Dijk DJ, Kronauer RE. Stability, precision, and near-24-hour period of the human circadian pacemaker. Science. 1999 Jun 25;284(5423):2177-81. doi: 10.1126/science.284.5423.2177.

  PMID: 10381883 BACKGROUND

Biospecimen

Retention: SAMPLES WITH DNA

Gingival tissue biopsy samples obtained from interproximal sites during clinically indicated periodontal procedures. Samples were immediately stored at -80°C for subsequent RNA extraction, gene expression analysis (RT-qPCR), protein analysis (Western blot), and cytokine quantification (ELISA).

MeSH Terms

Conditions

Gingivitis; Periodontitis; Inflammation

Condition Hierarchy (Ancestors)

Infections; Gingival Diseases; Periodontal Diseases; Mouth Diseases; Stomatognathic Diseases; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Study Officials

• Cuneyt A Aral, Professor, DDS, PhD

  Inonu University

  STUDY CHAIR

Study Design

• Study Type: observational
• Observational Model: CASE CONTROL
• Time Perspective: CROSS SECTIONAL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor, Department of Periodontology

Study Record Dates

• First Submitted: March 1, 2026
• First Posted: March 5, 2026
• Study Start: January 20, 2024
• Primary Completion: March 2, 2025
• Study Completion: December 1, 2025
• Last Updated: March 6, 2026

Record last verified: 2026-03

Locations

TU (1)