Effect of Propolis on Salivary Glands After Radiotherapy

To investigate the effects of increasing propolis doses on salivary glands exposed to radiotherapy (RT).

Thirty-seven rats were divided into 4 groups: The control group (G0, n: 7), G1 group (n: 10), G2 group (n: 10), and G3 group (n: 10). The rats in the G1 group received 15 Gray (Gy) RT only to the head and neck area. The rats in the G2 and G3 groups received 15 Gy RT for the head and neck area along with 100 mg/kg/ml and 200 mg/kg/ml of propolis. The parotid, submandibular, and sublingual glands of rats were immunohistochemically stained with aquaporin-1 (AQP-1) and aquaporin-5 (AQP-5). They were also evaluated for malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GPO), total antioxidant (TAS), and total oxidant status (TOS).

AQP-1 and AQP-5 values were highest in G0 group followed by G3, G2, and G1 groups in decreasing order. The MDA and TOS values were highest in G1 group, which was followed by G2, G3, and G0 groups. The highest GPO, SOD, and TAS values were observed in G0 group followed by G3, G2, and G1 groups in decreasing order.

It was found that propolis increased antioxidant products and decreased oxidative products in the salivary glands receiving RT in parallel with the dose increase. Similarly, in the groups receiving propolis, an increase in the immune expression of aquaporin molecules was detected in a dose-dependent manner. Based on these data, it could be stated that propolis has a healing effect on the salivary glands exposed to RT.