Background/aim: Total-body irradiation (TBI) doses in the range of 2-8 Gy are associated with a drop in peripheral blood counts, decreased bone marrow cellularity, and hematopoietic syndrome. Radiation mitigators must be safe for individuals likely to recover spontaneously.
Materials and methods: Female C57BL/6HNsd mice exposed to 9.0 and 9.15 Gy TBI, received intraperitoneal (10 mg/kg) JP4-039, a novel radiation mitigator, 24 hours after irradiation and were followed for hematopoietic recovery.
Results: Irradiated mice showed reduced peripheral blood lymphocytes and neutrophils and bone marrow cellularity at day 5. Serum electrolytes, liver and renal function tests showed no deleterious effect of JP4-039-after irradiation, and no reduction in survival compared to irradiated controls. Marrow recovery measured as cellularity, and hematopoietic colony-forming cells including primitive granulocyte-erythroid-megakaryocyte-monocytes (GEMM), reached pre-irradiation levels by day 30 in JP4-039 treated groups. Mice receiving single or multiple administrations of JP4-039 showed an early return of CFU-GEMM.
Conclusion: JP4-039 (GS-Nitroxide) is a safe radiation mitigator in mice warranting studies in larger animals and potentially a Phase I Clinical Trial.