Comparative investigation of the preventive effects of amifostine and melatonin on periodontal tissue destruction in rats with experimental periodontitis and radiotherapy

Aim: The aim of this study was to investigate the protective effects of amifostine and melatonin oxidatively, biochemically and histomorphometrically in rats with radiotherapy-induced experimental periodontitis. Material and Methods: 40 female Sprague-Dawley rats were divided into 5 groups: Control, Experimental periodontitis (Ep), Ep+Radiotherapy (Ep+Rt), Ep+Rt+Amifostine (Ep+Rt+Ami), Ep+Rt+Melatonin (Ep+Rt+Mel). The day after induction of periodontitis by ligature, a single dose of 5 Gray radiotherapy was administered. On the same day, treatments with amifostine (200 mg/kg) for 3 days and melatonin (10 mg/kg) for 15 days were started. At the end of the experiment, periodontal bone loss was measured by histomorphometry. RANKL, OPG and Caspase-3 activities were analyzed immunohistochemically and inflammatory cytokine (IL-1β, IL-10, IL-6, TNF-α) levels and oxidative stress (TOS/TAS) were analyzed biochemically in tissue homogenates. Results: It was observed that there was a significant difference in many biochemical parameters and oxidative stress levels between the control group and Ep+Rt (p<0.05). Alveolar bone destruction in the melatonin prophylaxis group was observed to be close to control (p>0.05). Melatonin significantly improved biochemical, histochemical, apoptotic and bone loss levels in irradiated experimental periodontitis rats (p<0.05). When comparing the two drug groups (Ep+Rt+Ami and Ep+Rt+Mel), no statistically significant difference was found at any parameter level (p>0.05). Conclusion: Radiotherapy has been shown to exacerbate periodontal damage at the oxidative, inflammatory and apoptotic levels, and preventive use of amifostine and melatonin significantly limits this destruction. Given the limited side effects of melatonin, it may be an alternative to amifostine.