Radioprotective and anti-diabetic effects of Costus speciosus and carnosine.

Purpose: To evaluate the possible radioprotective effect of Costus speciosus and carnosine as natural antioxidants in order to control the hyperglycemia developed in male albino rats exposed to acute oxidative stress induced by gamma radiation. Methods: Twenty-eight adult male albino rats were divided into four groups. The first group was taken as a control group, while the three other groups were exposed to γ irradiation at a single 7.5 Gy dose. Furthermore, the rats in the second and third groups were i.p. injected with Costus speciosus root powder and carnosine, respectively. On the 3rd day, after irradiation, the serum levels of glucose, insulin, C peptide, copper, iron, calcium, total antioxidant capacity (TAC) and malondialdehyde (MDA) were measureded. Results: The results revealed that exposure to γ irradiation induced significant increases in serum glucose, iron, and malondialdehyde. However, the levels of serum calcium, copper, total antioxidant capacity and insulin significantly decreased (p < 0.05). A significant decrease was observed in C peptide in the exposed group, compared to control group. All the test parameters indicate improvement after treatment with Costus speciosus and carnosine (p < 0.05). Conclusion: Costus speciosus and carnosine ameliorate the effect of gamma radiation, indicating their role as antidiabetic agents and radioprotectors; however, Costus speciosus was critically more efficient than carnosine. [ABSTRACT FROM AUTHOR]