The Role of Visfatin in Obesity and Periodontal Disease
Condition: Obesity; Periodontitis
MeSH terms: Periodontitis; Periodontal Diseases; Obesity
Study type: Observational

Summary: 
      Visfatin is an adipokine that plays an important role in immune functions as a growth factor,
      enzyme, and proinflammatory mediator. The investigators aimed to determine the levels of
      visfatin, interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) in gingival
      crevicular fluid (GCF) in both obese/non-obese patients, with/without generalized chronic
      periodontitis (GCP). Patients were categorized as obese (O) (n=31) or non-obese (nO) (n=19).
      Groups were divided into four subgroups according to periodontal conditions: (1)
      periodontally healthy without obesity (nO-Ctrl); (2) GCP without obesity (nO-CP); (3)
      periodontally healthy with obesity (O-Ctrl); and (4) GCP with obesity (O-CP). Demographic
      variables and anthropometric and laboratory data were recorded. Periodontal measurements were
      recorded at baseline and 3rd months after either non-surgical periodontal treatment or
      calorie restricted diet therapy. At the same time GCF samples were taken from patients to
      analyze TNF-alpha, IL-6, and visfatin levels.
    

Detailed description: 
      Overweightness and obesity are defined as the accumulation of fat in body tissues that might
      impair overall health. Adults are considered overweight if their body mass index (BMI,
      calculated as weight in kg/[height in meters]2) is ≥ 25 and obese if BMI ≥ 30 kg/m2. The
      prevalence of overweightness and obesity has increased worldwide during recent decades.

      Obesity is usually related to a chronic low-grade systemic inflammation resulting in
      significant changes in the concentrations of cytokines and hormones, which subsequently leads
      to the development of obesity-linked disorders, including insulin resistance, type II
      diabetes, cardiovascular diseases, dyslipidemia, and metabolic syndrome. Since the host
      response is among the most crucial factors affecting the pathogenesis of periodontal disease,
      multiple studies have addressed the possible associations between BMI, overweightness,
      obesity, diabetes, the serum level of lipids, cholesterol, and periodontal breakdown, with
      mixed results. Many studies have demonstrated a positive association between obesity and
      periodontitis and suggested that obesity-related inflammation might promote periodontitis by
      secretion of inflammatory markers by the adipose tissue, which might subsequently increase
      gingival inflammation. The association between obesity and periodontal disease is based on
      the amassing of white adipose tissue (WAT) and increased secretion levels of adipokines from
      WAT.

      WAT is an energy storage organ with some metabolic activities, participating in the endocrine
      and secretory systems. WAT secretes several immune-modulatory adipokine molecules, such as
      adiponectin, leptin, visfatin, resistin, chemerin, tumor necrosis factor-alpha (TNF-alpha),
      interleukin-1β (IL-1β), and interleukin-6 (IL-6). It has been found that these molecules are
      involved in a wide range of physiologic and pathologic processes, including immunity and
      inflammation. Thus, cytokines and hormones released from adipose tissue might play a role in
      the destruction of periodontal tissue by inducing hyperinflammatory responses.

      Visfatin is a multi-potential mediator that functions as a growth factor, cytokine, an enzyme
      with a role in energy metabolism, and as a proinflammatory mediator. It is mainly released
      from adipose tissue, especially from macrophages, and can also be released from lymphocytes,
      dendritic, muscle, and bone marrow cells. Visfatin has an important role in the regulation of
      the immune response. Visfatin inhibits neutrophil apoptosis during inflammation and increases
      TNF-alpha, IL-1β, and IL-6 levels. The expression of visfatin is increased under inflammatory
      conditions, such as rheumatoid arthritis, cardiovascular diseases, type-II diabetes mellitus,
      and periodontal disease.

      Although several studies have demonstrated the relationship between periodontitis and
      obesity, no study has evaluated the levels of visfatin in gingival crevicular fluid (GCF) in
      obese individuals with periodontitis. Increased adipocytes levels, such as visfatin, cause
      secretion of cytokines, which are known to play an important role in periodontitis, and might
      trigger periodontitis formation and development.

      Therefore, the main objective of this study was to analyze the levels of visfatin, IL-6, and
      TNF-alpha in obese and non-obese individuals, with or without generalized chronic
      periodontitis (GCP). Secondarily, the investigators aimed to evaluate metabolic and clinical
      periodontal parameters, and also clarify the relationship between these parameters and
      adipocytokines. The hypothesis is that adipocytokine molecules are involved in the
      pathogenesis of inflammatory diseases; if true, individuals who are obese with periodontitis
      would present increased levels of visfatin, IL-6, and TNF-alpha in their GCF.
    

Intervention name(s): Phase I Periodontal therapy; Metabolic control
Intervention type(s): Procedure; Dietary Supplement
Intervention description(s): Oral hygiene instuction, scaling and root planning; Calorie restricted diet
Observational model: Case-Control
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        The 195 patients diagnosed with obesity in the outpatient clinics of Endocrinology and
        Metabolic Diseases Department, Ataturk Hospital, Turkey, were potential candidates and were
        interviewed according to our case definition and invited to be included in the study.
        Thirty-one of 195 volunteers accepted and signed the informed study protocol and took part
        in the study. All individuals were thoroughly informed of the nature, potential risks, and
        benefits of their participation in the study before providing their informed consent.

        In the same period, 100 consecutive non-obese patients were screened from the Department of
        Periodontology, Faculty of Dentistry, Gazi University, Turkey, who were systemically
        healthy and fulfilled the inclusion criteria, of which 19 agreed to participate.
      
Biospecimen description: 
      Gingival crevicular fluid
    
Keywords: obesity; periodontitis; cytokines