Gamma-tocotrienol, a radiation prophylaxis agent, induces high levels of granulocyte colony-stimulating factor.

Gamma-tocotrienol (GT3), a promising radioprotectant, is shown to protect CD2F1 mice from radiation-induced neutropenia and thrombocytopenia when given 24h prior to total-body irradiation. GT3 also is shown to increase white blood cells (WBC) and absolute neutrophil counts (ANC) transiently in peripheral blood. We hypothesized that increases in WBC and ANC may involve stimulation of hematopoiesis possibly by cytokines and growth factors.

Amelioration of radiation-induced hematopoietic and gastrointestinal damage by Ex-RAD(R) in mice.

The aim of the present study was to assess recovery from hematopoietic and gastrointestinal damage by Ex-RAD(®), also known as ON01210.Na (4-carboxystyryl-4-chlorobenzylsulfone, sodium salt), after total body radiation. In our previous study, we reported that Ex-RAD, a small-molecule radioprotectant, enhances survival of mice exposed to gamma radiation, and prevents radiation-induced apoptosis as measured by the inhibition of radiation-induced protein 53 (p53) expression in cultured cells.

Gamma-tocotrienol protects hematopoietic stem and progenitor cells in mice after total-body irradiation.

We analyzed the radioprotective effects of gamma-tocotrienol (GT3) on hematopoietic stem cells (HSCs) and progenitor cells (HPCs) in sublethally irradiated mice. Flow cytometry analysis indicated that radiation depleted HPCs (c-Kit(+), Lin(-)) to 40% at days 2 and 4 after total-body irradiation (TBI) in all treatment groups. The HPC numbers in GT3-treated mice recovered almost completely (90%) at day 7 but remained depleted in vehicle-treated mice (30%) even at day 13 after TBI.