Isolation of (+)-catechin and (-)-epicatechin from Actinidia arguta as bone marrow cell proliferation promoting compounds.

The MeOH extract of stems of Actinidia arguta promoted proliferation of cultured bone marrow cells and stimulated formation of myeloid colonies from bone marrow cells. (+)-Catechin ( 1) and (-)-epicatechin ( 2) were isolated as active compounds from the MeOH extract. Compounds 1 and 2 stimulated the cell proliferation in a concentration-dependent manner in the range of 1 to 100 mg/mL. Compounds 1 and 2 also stimulated formation of myeloid colonies and enhanced the effect of interleukin-3 (IL-3) to increase the number of colony forming-units in culture (CFU-c). In an ex vivo experiment using a model mouse of decreasing bone marrow functions, orally administrated 1 (100 mg/kg/day) stimulated IL-3-induced CFU-c formation of the bone marrow cells.