ABSTRACT
BACKGROUND: Lutein, a carotenoid compound, has previously been studied for its antioxidant and medicinal properties as well as the moderate protection it confers against gamma radiation. This study aimed at evaluating the effects of lutein against radiation-induced hematological and biochemical changes in mice. METHODS: The optimized dose of the compound was orally administered for 15 days, and the mice were irradiated (6 Gy) on day 15 after the administration of the compound. The groups were divided (6 mice in each group) into normal control, radiation control, gallic acid control, 10% DMSO control, lutein control, and irradiated groups pretreated with gallic acid, 10% DMSO, and lutein. Gallic acid was used to maintain a standard since it is a proven radioprotector. Within 24 hours post irradiation, the animals were anesthetized and sacrificed. The hematological, biochemical, and antioxidant changes were determined using suitable methods. Data were analyzed by the Kaplan-Meier curve (log-rank test) and ANOVA (the Tukey test). The independent t test was used to compare the independent groups. SPSS (ver. 16) was employed. RESULTS: Maximum survival was observed with a dose of 250 mg/kg b.wt lutein. The total leukocyte count and the percentage lymphocyte count exhibited a significant decline in the irradiated groups pretreated with gallic acid and lutein in comparison to their controls, whereas the percentage granulocyte count showed a significant rise. Antioxidant activity had markedly declined in the irradiated groups, indicating oxidative stress. Lutein pretreatment reduced the damage and maintained the antioxidant system. CONCLUSION: The present study suggests a protective role for lutein in palliating radiation-induced oxidative changes and maintaining the antioxidant system in vivo.
ABSTRACT
OBJECTIVES: Radiation-induced hematological, biochemical, and cytogenetic damages to the normal cells are major concerns in the field of radiotherapy. The carotenoids and their derivatives have been the source of antioxidants with wide range of medicinal applications. The objective is to evaluate the protective effects of lutein, a carotenoid, against radiation-induced cellular and tissue damages. METHODS: Swiss albino mice were grouped into 5, 50, 250, and 500 mg/kg b.wt. of lutein treatment groups, a sham and vehicle control group. The groups were irradiated with a lethal dose of 10 Gy y'-radiation. The mortality was recorded for 30 days to optimize the protective dose against radiation. The mice were administered with the compound orally for 15 consecutive days and irradiated with a sublethal dose of 6Gy. The hematological changes in blood and antioxidant parameters were determined in liver, kidney homogenates, and hemolysate/serum. The hematological parameters were recorded using an automated cell counter. The antioxidants such as malondialdehyde (MDA), glutathione (GSH), superoxide dismutase, catalase, glutathione peroxidase and glutathione-S-transferase were spectrophotometrically determined. RESULTS: The red blood cell, white blood cell count, lymphocyte count, hemoglobin, platelet levels, and hematocrit value were found to be decreased in the irradiated groups. Lutein pretreatment maintains near-normal levels of these parameters indicating resistance/recovery from the radiation-induced damages. The antioxidant levels were found to be reduced in all the irradiated groups. However, lutein pretreatment (50 mg/kg b.wt.) has increased the catalase activity of hemolysate. Lutein pretreatment has reduced the MDA levels in hemolysate, when administered at doses of 5, 250, and 500 mg/kg b.wt. in comparison to its control. CONCLUSION: The study demonstrates the radioprotective potential of lutein by maintaining the hematological and antioxidant homeostasis.