Protective Effect of Lecithinized SOD on Reactive Oxygen Species-Induced Xerostomia

Abstract

Reactive oxygen species (ROS) are believed to be involved in radiation-induced xerostomia, and the application of antioxidants may be a promising method for treating patients suffering from salivary gland dysfunction. In this study, we examined the ability of the antioxidant superoxide dismutase (SOD) to restore radiation-induced salivary gland dysfunction using a mouse model of radiation-induced salivary gland hypofunction and ultraviolet B (UVB)-irradiated human salivary gland cells. We administered lecithinized SOD (PC-SOD) prior to and after irradiation and measured the amount of saliva secreted. To confirm ROS generation, flow cytometry was performed using an oxidant-sensitive fluorescent dye, dihydroethidium, and CM-H(2)DCFDA. While no significant decrease in saliva secretion was observed after irradiation in the mice that were treated with PC-SOD, a significant reduction in saliva secretion was noted in the irradiated mice that were not treated with PC-SOD. Furthermore, flow cytometry clearly revealed that PC-SOD eliminated superoxide (O(2)(-)) induced by UVB radiation. These results suggested that PC-SOD may protect against exocrine gland dysfunction induced by radiation, presumably by rapidly converting O(2)(-) to hydrogen peroxide. We believe that our results may advance the potential application of antioxidants for the prevention of ROS-induced xerostomia.

A dose-dependent perturbation in cardiac energy metabolism is linked to radiation-induced ischemic heart disease in Mayak nuclear workers

“…As oxidative stress-induced protein modifications such as carbonylation lead to increased protein degradation [28] or inactivation [29], increased oxidation of mitochondrial proteins may explain the vigorous downregulation in their expression seen in this study.…”

Mitigation of radiation-induced lung injury by genistein and EUK-207

“…The superoxide dismutases (SOD) are a family of metalloprotein enzymes that have a significant role in protection from oxidative damage. Since their discovery in 1969 (McCord and Fridovich 1969, 1969), there have been several reports that SOD can decrease radiation damage in a wide range of biological systems including lung (Abou-Seif et al 2003, Epperly et al 2000, Epperly et al 2001, Kang et al 2003, Khan et al 2003, Petkau 1987, Quinlan et al 1994, Rabbani et al 2005, Tai et al 2009, Tsan 1997). SOD functions by converting superoxide to H 2 O 2 and O 2 .…”

Research progress in the radioprotective effect of superoxide dismutase

“…By means of flow cytometry, it was found that the sharp reduction of salivary secretion in the mice irradiated at head-and-neck region was caused by the overproduction of ROS resulting from radiation. However, this phenomenon was not observed in the group of mice with PC-SOD (lecithinized SOD) treatment due to the capability of PC-SOD to scavenge  2 O during the whole experimental process (42). Subsequently, another study by Nagler et al showed a similar trend in the Wistar rats administered with Mn-SOD, which showed a dramatic resistance against hyposalivation induced by local headand-neck radiation (43).…”