Protective action of picroliv isolated from Picrorhiza kurroa against radiation clastogenecity on mice and cyclophosphamide-induced cytotoxicity in Allium cepa Root Papiya Bigoniya, Ankita Warathe, Chandra Shekar Singh Journal of Radiation and Cancer Research 2019 10(1):58-65 Objective: Wide-scale cell death, following chemo and radiation therapy, is a major concern in clinical therapy of cancer. The need to identify agents with a potential for chemo and radioprotective potential has assumed great importance. The study aims at the evaluation of the efficacy of picroliv, a potent antioxidant derived from the plant Picrorhiza kurroa, as cyto- and radioprotector. Materials and Methods: Picroliv was fed to mice in a dose of 20 and 30 mg/kg, i.p. daily for 15 days following 4 Gy gamma rays exposure. Body weight, mortality, and hematology were assessed along with endogenous spleen colony-forming unit (CFU) and micronucleus (MN) scoring. In vitro cytoprotective activity was assessed on Allium cepa root meristem growth parameters against cyclophosphamide-induced genotoxicity by determination of mitotic index (MI) and chromosome aberrations (CA). Results: Picroliv treatment resulted in reduced body weight loss, recovery of hematological parameters, increased CFU preservation, and reduced MN expression. Picroliv caused an increase in root length and number of A. cepa simultaneously exposed with cyclophosphamide. Cyclophosphamide-induced cellular damage as measured by MI, and CA was significantly less. Picroliv at 10 mg/ml concentration showed normal dividing cells with few fragments, and sticky chromosome reversing the severe cytotoxicity of cyclophosphamide expressed with chromosome fragmentation, vagrant, sticky, and C-anaphase chromosomes. Conclusion: The results of this study strongly suggest picroliv to be a promising agent for ameliorating injury, following radiation and chemotherapy. The potent antioxidant, hepatoprotective, and immune-modulatory properties of picroliv may be responsible for the apparent cyto- and radioprotective activity.