Investigation of endoplasmic reticulum stress in gingiva tissues of diabetes mellitus and periodontitis patients

Objective: Endoplasmic reticulum (ER) stress increases in chronic inflammatory diseases. Diabetes Mellitus (DM) and periodontitis are also chronic inflammatory diseases. In this study, it was aimed to investigate the endoplasmic reticulum stress in gingival tissue samples taken from periodontitis patients with systemic Diabetes Mellitus, systemically healthy periodontitis patients and systemically and peridontally healthy patients. Method: A total of 48 individuals, 24 females and 24 males, with resective gingival surgery indications (such as gingivectomy, crown neck lengthening) were included in this study. The patients were divided into three groups as periodontitis with DM (n=16), periodontitis (n=16) and healthy (n=16). Periodontal clinical parameters of the patients were measured and recorded before their periodontal treatments. Gingival tissue samples taken from patients were kept at -80oC until the day of analysis. From the homogenates obtained from tissue samples, GRP78, PERK, eIF2α and ATF4 were analyzed by Polymerase Chain Reaction analysis; Bcl-2, Bax, caspase-3 genes were analyzed by Western blot analysis. Results: The expression levels of ER stress (GRP78, eIF2α and ATF4) and apoptosis (Bax and caspase-3) genes were significantly higher in the periodontitis patient group with DM compared to the periodontitis and healthy group (p<0,05). The lowest expression levels were found in the healthy group (p<0,05). Conclusion: Increased ER stress and apoptosis were observed in both DM and periodontitis groups. However, the highest increase is found in periodontitis patients with DM. Keywords: ER stress, Periodontitis, Diabetes Mellitus, PERK