RESUMO
PURPOSE: The present work was intended to evaluate the radioprotective effect of quercetin against gamma radiation-induced oxidative stress on red blood cells (RBC). MATERIALS AND METHODS: Swiss albino male mice were treated with quercetin (100 mg/kg body wt) for three consecutive days prior to 5 Gy (60)Co-gamma irradiation. RBC was isolated to estimate the level of intracellular reactive oxygen species (ROS), membrane lipid peroxidation (LPO), intracellular reduced glutathione (GSH), mean corpuscular hemoglobin concentration (MCHC), osmotic fragility and morphological alterations by atomic force microscope (AFM). RESULTS: Irradiation increased intracellular ROS and membrane LPO whereas it decreased the intracellular GSH. Quercetin pretreatment ameliorated these alterations. The MCHC value decreased after irradiation whereas quercetin pretreatment restored it. The average osmotic fragility (H50) and the maximum rate of hemolysis (dH/dC)max increased after irradiation. Quercetin pretreatment decreased the H50 and (dH/dC)max. The AFM study showed that irradiation transformed RBC from biconcave to echinocytes, increased their surface roughness and decreased the vertical distance whereas pretreatment of quercetin significantly prevented both the alterations. CONCLUSIONS: Gamma radiation produced ROS and LPO which rendered oxidative stress and ultimately damaged RBC whereas quercetin ameliorated these changes and protected RBC from radiation-mediated damage.
