Immunolocalization of heme oxygenase-1 in periodontal diseases

Chronic periodontitis is an inflammatory condition of supporting tissues initiated by organisms in dental plaque. The reactive oxygen species and free radicals mediate connective tissue destruction in periodontitis. In order to counteract the free radical mediated tissue damage, numerous antioxidant mechanisms exist within the host. One such system is heme oxygenase enzymes. Heme oxygenase is the key enzyme involved in catabolism of heme. It cleaves the heme molecule to yield equimolar amounts of biliverdin, carbon monoxide, and iron. These end products act as important scavengers of reactive oxygen metabolites. Increased heme oxygenase expression has been identified in inflammatory condition, such as pancreatitis, diabetes, nephritis, and atherosclerosis. Since chronic periodontitis is one such inflammatory condition, we assessed the expression of heme oxygenase-1, in smokers and periodontitis group using immunohistochemistry technique.

The aim of this study is to compare the expression of heme oxygenase-1 in patients with healthy periodontium, periodontitis and smokers.

Gingival tissue samples were taken from 30 patients, who were divided into three groups healthy controls (n = 10), chronic periodontitis (n = 10), and smokers with chronic periodontitis (n = 10). All the samples were subjected to immunohistochemical staining using the antiheme oxygenase-1 antibody and were tested for efficiency by staining a positive control (prostate cancer tissue sections) and a negative control. The results were tabulated and analyzed.

Our results showed increased expression of heme oxygenase-1 in the gingival tissue samples taken from smokers compared with periodontitis and healthy tissue.

The results of our study is an increasing evidence of involvement of antioxidant enzymes like heme oxygenase-1 in periodontal inflammation and their implication for treatment of chronic periodontitis.