Abstract
We found that AGL-517, an α-galactosylceramide (α-GalCer), possesses potent radioprotective activities against mice irradiated with 9 Gy of X-ray in contrast to its having no effect on mice irradiated with 10 Gy of X-ray. The result suggested the possibility that α-GalCers protect mice from bone marrow death. To examine this possibility, we examined the effects of two kinds of α- and β-GalCers on counts of palatelets (PLT) and white blood cells (WBC) in the peripheral blood of normal mice and mice irradiated in a whole body with 5 Gy of X-ray. α-GalCers significantly increased the PLT and WBC counts of both mice in comparison with the vehicle-treated group, and their potencies were stronger than those of their β-types. Furthermore, we evaluated the in vitro bone marrow cell-proliferation stimulatory activities of four kinds of GalCers, and found that α-GalCers show stronger stimulatory effects than β-types. These results demonstrate that the α-configuration of GalCers plays an important role in the manifestation of the above-mentioned activities of GalCers. The results also suggest that α-GalCers may be useful as hematopoietic stimulators as well as radioprotective agents.
