The Protective Efficacy of Hesperidin and Thymol on Radiation-Induced Submandibular Gland Damage

Objective: The purpose of this study was to employ biochemical, histopathological, and immunohistochemical methods to reveal the effectiveness of hesperidin and thymol in preventing radiotherapy-associated submandibular gland injury. Methods: A total of 48 female Sprague Dawley rats were randomly assigned into six groups of eight animals each. Group 1 represented the control group. Group 2 was regarded as hesperidin Group, and the rats received only hesperidin. Group 3 was regarded as thymol Group, and the rats received only thymol. Group 4 was regarded as a Radiotherapy Group, and the rats were exposed to radiotherapy at a dose of 15 Gy. Group 5 was regarded as hesperidin + Radiotherapy Group, and rats received hesperidin at a dose of 100 mg/kg daily for 1 week prior to radiotherapy exposition. Group 6 was regarded as thymol + Radiotherapy Group, and rats received thymol at a dose of 100 mg/kg daily for 1 week prior to radiotherapy exposition. Rats were sacrificed after radiotherapy and submandibular glands were dissected for biochemical and immunohistochemical evaluations. Results: We have shown that, thanks to their strong antioxidant and anti-inflammatory properties, hesperidin and thymol minimize the damage caused by radiation toxicity by decreasing oxidant levels and increasing antioxidant enzyme levels in the submandibular gland. We found that thymol showed more protective activity than hesperidin in terms of effectiveness on radiation toxicity. Conclusion: Hesperidin and thymol exhibit histopathological, immunochemical, and biochemical protection against radiation-related submandibular gland injury. To our knowledge, this is the first study in the literature in this field.