Histological and Immunohistochemical Study of Selenium Regenerative Effect on Submandibular and Sublingual Glands of Aging Rats

Background: The role of Selenium as an antioxidant has become a point of interest for its importance in prevention of cancer and other systemic diseases especially those associated with aging.
Objectives: The aim of the present investigation was to investigate the effect of Selenium supplementation on the submandibular and sublingual salivary glands of aging rats through:
1- Histological examination.
2- Immunohistochemical localization of Ki67.
Materials and Methods: Thirty young adult male albino rats with body weight ranged from 80-110 gram and of 2 month age were used and divided into the following groups. Group I (control group): Consisted of 20 rats, subdivided into 2 subgroups. Group I.1:10 animals were sacrificed after one month to serve as young controls. Group I.2:10 animals were left till the end of the experiment to serve as old controls. Group II: 10 animals received Selenium 150 µg/kg diet for the whole experimental period. The experiment lasted for 9 months.
Results: histological results revealed that aging caused devastating effects on the histological structure of submandibular and sublingual salivary glands. Selenium markedly modulated the action of aging process and increased the regenerative capacity of submandibular and sublingual glands. According to expression intensity of Ki67 stain in submandibular and sublingual glands, there was statistically significant difference between young, selenium and old groups. In general, expression intensity of Ki67 stain was the highest in the young control group followed by selenium group and lowest in old control group. Also, ki67 expression was significantly higher in sublingual than submandibular glands.
Conclusions: Selenium was documented to have a powerful and beneficial antiaging effect. This faced lights around the promising role of selenium in the new era of regenerative medicine. Sublingual gland was more resistant to regressive changes of aging than submandibular gland.