Orange peels and Chlorella vulgaris supplementation ameliorate gamma radiation-induced oxidative stress by regulating TGF-β and NOX2/NOX4 signaling pathways.

Numerous studies revealed that Chlorella vulgaris and orange peels are potential sources for many valuable compounds such as flavonoids, which are natural polyphenols with antioxidant capacities that lessen oxidative stress via suppressing ROS levels. Thus, this study was designed to investigate their radioprotective efficiency either alone or in combination as natural food supplements. Sixty-four male Albino rats were divided into eight groups (n = 8) as follows: control, orange peel (10% in diet), C. vulgaris (1% in diet), orange peel + C. vulgaris, gamma irradiated (2Gy twice per week up to 8Gy), orange peel + gamma irradiation, C. vulgaris + gamma irradiation, and orange peel + C. vulgaris + gamma irradiation. After the experiment, blood serums were collected for biochemical analysis, whole bloods were collected for blood picture, bone marrows were collected for GSH, MDA, TGF-β, NOX2 and NOX4, and liver tissues were collected for histopathological evaluation. Current study revealed that exposure to gamma irradiation induced a significant disturbance in liver function markers (ALT and AST), kidney function markers (urea and creatinine), cholesterol and triglycerides levels in serum. In addition, a significant decrease in WBCs, RBCs, PLT, and Hb in blood of irradiated rats. Moreover, a significant elevation in TGF-β, NOX2, NOX4 activities, and MDA level, while showed a marked decrease in GSH concentration. Furthermore, hepatic inflammation appeared in the histopathological examination. Orange peels or C. vulgaris treatments showed acceptable amelioration in all measured parameters, combination between orange peels and C. vulgaris showed statistically significant additive amelioration in radiation induced disturbance.