ISOLATION AND IDENTIFICATION OF HEMATOPOIETIC STEM CELL-STIMULATING SUBSTANCES FROM KAMPO (JAPANESE HERBAL) MEDICINE, JUZEN-TAIHO-TO

We have previously found that TJ-48 has the capacity to accelerate rec overy from hematopoietic injury induced by radiation and the anti-canc er drug mitomycin C (MMC). The effects are found to be due to its stim ulation of spleen colony-forming unit (CFU-S) counts on day 14. In the present study, we attempt to isolate and purify the active components in TJ-48 extracts using a new in vitro hematopoietic stem cell (HSC) assay method, n-Hexane extract from TJ-48 shows a significant stimulat ory activity. The extract is further fractionated by silica gel chroma tography and HPLC in order to identify its active components. H-1-NMR and GC-EIMS indicate that the active fraction is composed of free fatt y acids (oleic acid and linolenic acid). When 27 kinds of free fatty a cids (commercially available) are tested using the HSC proliferating a ssay, oleic acid, elaidic acid, and linolenic acid are found to have p otent activity. The administration of oleic acid to MMC-treated mice e nhances CFU-S counts on days 8 and 14 to twice the control group. Thes e findings strongly suggest that fatty acids contained in TJ-48 active ly promote the proliferation of HSCs. Although many mechanisms seem to be involved in the stimulation of HSC proliferation, we speculate tha t at least one of the signals is mediated by stromal cells, rather tha n any direct interaction with the HSCs. (C) 1997 by The American Socie ty of Hematology.